I decided to collect a list of the Mandelbulb 3D fractalists on Deviant Art.  It's for no purpose other than to get a really informal & rough idea how many of us there are. Here's what I came up with.

Each entry links to the Deviant's gallery.  If you'd like to be added or removed just let me know.

*0cQfe77a588aeM  ~0Encrypted0  ~11-73-3-33  ~2old4gamez  
~3x3  ~a-j-s  ~abbasy  ~aberrantbehavior  
~Abstraqted  *Ace60  ~Actionjack52  ~actionjosh  
*aereol  ~aerphis  ~agent48  =alepainkiller  
~AlexisDale423  *allthenightlong  *Andrea1981G  =AnnaKirsten  
~annemaccat  ~arcadian7  ~artao  ~arthurxII  
~Artistic-Futuristic  ~ArtKangem  *aRTWORKbYgnbARNES  ~Aseryith  
~aspidina  ~asydhouse  ~Atabeyli  *AureliusCat  
~Autus  *axolotl7  ~Baddad  ~batjorge  
~beaudeeley  ~bermarte  ~bezo97  *bib993  
~bizcut  ~BlackBirdsFeather  =Blazemorioz  *bluefish3d  
~bo-dion  *boot-cheese-3000  ~borosyl  ~BrokenChaoz  
*brunopita  ~Bull53Y3  ~bunnywithrose  *ButtercupSaiyan  
~bytedreams  *C-91  ~cab1n  *Capstoned  
*carlahoon  ~caseycole11  `Casperium  *catelee2u  
~cgoa  ~chickenmilky  ~ciokkolata  *cloudlabs  
*Cluke111  ~ClydeFrogDA  ~CMA3D  *CMDRCHAOS  
*CO99A5  =CoffeeToffeeSquirrel  ~Coolok  ~Coterabeth  
~CPMacD  ~crazyaboutbryce  ~Croftka  ~crotafang  
~CryptFiend  ~crypticfragments  *Cygam-7  ~D3mQN  
~D3ST72  *Daeurth  *dainbramage1  ~DarK--MatteR  
=dark-beam  ~DarkMask  ~davidmcbride  *daxusflashlight  
~DDDPhoto  ~DeaconStone  ~DeirdreReynolds  ~desdentado  
~Devin74  *Digithalie  *Direct2Brain  ~DJDesco  
~djeaton3162  *dlandi  ~dogsdinner  ~donanubis  
*DorianoArt  ~DSMeskalito  *dspwhite  DsyneGrafix  
*Eccoton  ~echosoflife  ~Ectoplaz  ~Edo555  
~egehlin  ~electricdawn  ~Elegene  *EliseEnchanted  
~ellenm1  ~emiya89  ~Enigmatuz  ~Esko911  
~EstylaX  ~eugova  *evoluzione  ~EyesOfAcheron  
~FAIA-Fractals  ~famorphing  ~farnea  ~Feeriee13  
~fengda2870  *Fiery-Fire  ~findzha  =Flutterbr0  
~flyashy  ~flytier  ~FomalhautB  ~Fourpillars  
~Fractal-Kiss  *fractalbeke  *FractalDesire  *fractalfiend  
~fractalfractal  *FractsSH  ~fractzxirus  ~FracZky  
~fragmentNull  ~fram1963  ~Francular  *fraterchaos  
~FRATMEX  ~frawgzdezignz  ~fraxialmadness3  ~FreakofNature81  
*Frozencapsule  ~FunkMastaYoda  ~GalerieVirtuelle  *gateman45  
~geisty  ~gentle-strength  ~GermanFafian  ~GetHighOrDie  
*GhostWriterSociety  ~Gibson125  ~glaktor  *GLO-HE  
~gmlab  ~gobrain365  *Golubaja  *GrahamSym  
~GraphicsTechnician  ~GreyoneW  *GrungeTV  ~guagapunyaimel  
~Guan-pued  ~Guard-of-Stone  =GypsyH  *HalTenny  
`HazelCraft  ~hck112  ~heldenlama  *helice93  
~HenryBR  ~HeroOfDisaster  ~HirurgUlic  *hmn  
~HolloW1ShoT  ~Holzernerwelt  ~hubbabub  ~Humble-Novice  
~hyakugojuuichi  ~hyguy87  ~hyperben2  ~hypnogoddess  
~Iamtoo  ~ianjam  *im1happy  ~imokurnot  
~ineedfire  ~INITZS  ~inkydigit  ~innac  
~InsidiouslyJake  ~isbutisnot  =J-R-M-N-K-E  ~JadedIceStorm  
*jadenyc  =JahPickney  ~janhein  ~Jason-C  
~jawoltze  ~jccrfractals  ~jcGuarneros  ~Jillianelf  
=jim373  ~jim88bro  ~jimami  ~Jing-reed  
~jjordan12  ~JohnSimonRitchie  *joshpurple-Gassy  *jost1  
~jpjunk  *JuanCarlosDeLaVega  *jucarbi  ~JulesAlbertPol  
~julianreiss  ~junkdogAP  *Kaeltyk  *Karkan  
~kawardi  *kc267267  ~keymastercz  ~kimsmile  
~Klytia70  ~knightkight69  ~knightyFF  *KoAltaiTeMaunga  
~KPEKEP  ~kr0mat1k  *krigl  ~KRISTALIUM  
~KrzysztofMarczak  ~lady-AquaLena  ~lala-yonjia  *lar3ryca  
~Laurent-Blanc  =LaxmiJayaraj  ~leguen  ~Len1  
*LeonieZurakowsky  *LeXXe  ~LightBulbMoon  ~LikeJak  
*Lior-Art  *Liuanta  ~LLFlash  ~LMarkoya  
~loboto  ~lobs2  ~love1008  ~LovingLivingLife  
~lsergius10  ~lymar  *mac2010  *makepeaceart  
~MakinMagic  *MalDudemaker  ~mandalamker  ~mandelbrat  
~MandelCr8tor  ~MandelFish  ~Mandelscape  *MANDELWERK  
~marecaca  ~mario837  *Mark-Rezyka  =MarkJayBee  
*MarysartandPhotos  ~MasterAlbus3d  ~mateuszmorawski  ~mathematical-art  
*matrix2003  ~mauxuam  ~Mc-Gill  ~mediphysical  
~mehrdadart  *Melen  *MeLinFrance  ~mental2500  
~mephisto69  ~Metamodernism  ~mfuck  =MickHogan  
~MidnightFairie  *MiffinFonts  ~miguelnpg  ~mikey1964  
~mikitosevski  ~milleniumsentry  ~mindset43  ~MindsEye69  
~MindStep  ~mjdezo  *montag451  *moonhigh  
*morbidorbits  ~MPalacios  ~MrAries23  ~mrdeforrest  
~Muld48  =mutequacky  ~n-to-infty  ~nachoriesco  
~Naviretlav  ~Ncmprhnsbl  ~nebula32  *nemitode  
*neoshamballa  ~newbie23d  *nic022  ~Nietoshka  
~NightmareTF  ~nikitko13  ~NivelFish  ~NoEyedSquareGuy  
~Nosciel  ~Nostrabastus  ~NUListONE  ~okonik  
~onirophase  ~oppenheimer  ~Osipenkov  ~P41nM4k3r  
*paradox8reality  *PaulBaack  ~PeaceFrog777  *peinturealuile  
~PersistentAura  ~PeterPan81  ~Ph4nt4sm4ge  *philipbrunner  
*phoenixkeyblack  *PhotoComix2  *piritipany  ~pixwizart  
~plantm  ~pondcypress  ~Pontigary  ~popol4444  
~PR-Imagery  ~Preach-it  ~Project-GammaRay  ~Prokofiev2  
~PRSman  psion005  ~PsySun  ~purpleplane  
~Quie-Scent  ~rabidmoon  ~radlowsky  ~Raydianze  
=raysheaf  ~reciprocated  ~redbeltboxer  ~Redhed1  
~ReFa1  ~rfschenk  ~RhaalDev  ~richardPfeynman  
~rmrossa  ~rockyrakster  ~Rowratty  ~rueD  
~RV-TIDE  *rvallync  ~rydena  ~Sacredvine  
~SavannaW  ~schizo604  ~Schmiegel  ~SciFiArtMan  
~seied  ~Sekiro  ~serdartan  =shoughad  
~shutupandwhisper  ~SidicusMaximus  ~Silberstreif1905  ~silencefreedom  
*SilentCicada  ~Silmarilias  ~silverb  ~silverdragonrs  
*singmus  ~siriusstarsage  *SjerZ  ~SJS02  
~skulkey  =skyzyk  ~Snow-Fx  ~SnowblindFrog  
~SoberDreamer  ~solark  *Soldeus  ~somnl  
~SourSomethings  *Spamkiller  *SpinningAngel  ~stardust4ever  
*StaringDownTheVast  ~StarTrekOmega  ~stebev  *StellaTheStarDesign  
*Stereocyclop  ~Sternenmaschinebine  ~Stuart203  *SubtleC  
~SugarJen1  `SuicideBySafetyPin  ~svenart  ~sweetmaryfractals  
*synapsesp27  *Szellorozsa  ~TABASCO-RAREMASTER  ~Tahyon  
~Taojoe  ~Tectix  =teddybearcholla  ~teleportsofia  
*terforpova  ~TexArcana1962  ~the-Eggy  ~TheAstro  
~thehiddenworld  *Theli-at  ~TheLivingTree  ~Thenit  
*theslider  ~Thumaszz  =TiamatHeart  ~tiffrmc720  
*timemit  ~timthecat  *tina1138  ~TjeuvanBussel  
~tomlask  `TomWilcox  ~tonnytewart20  ~TonyDemot  
=Topas2012  =ToxicDwarf  ~Trance-Plant  ~trveviking  
~Tysel  *ugnivers  ~ulliroyal  ~ultrareality  
*Undead-Academy  ~vagabondvagrant  ~Valdemaras  ~VanlindtMarc  
~veldor60  ~vepman  *VickyM72  ~viperv6  
~Vitaloverdose  ~vmulligan  *VolatilePlums  ~walkthecreativepath  
~whateverscoolwithme  *whendt  ~wildekyote  *Will3Style  
*willclark218  *WilliamPilgrim  ~wolfwings1  ~wtdx  
*Xantipa2  ~xKLUSiV7  ~xlykantrophx  *xXWintersDescent  
`XyrusWorx  ~YewTree  ~youbang  ~YuryKyssa  
~zhar-ptizza  *ZoeUna  ~zozzy-zebra  ~zukuthegreat  

The list is based on the membership of four Groups dedicated to Mandelbulb 3D:

Mandelbulb3d
Mandelbulbers
Mandelbulbs
Mandelbulbfractals

I've also added a handful of MB3D fractalists that do not belong to these groups.

My apologies to the two entries whose IDs generate an emoticon - I had to remove your '=' prefix

484 IDs on the list