Miranda NG is designed, written & supported by (in alphabetical order):

Sergey Bolkhovskoy aka Elzor
Alexander Gavrilov aka dartraiden
Alexander Gluzsky aka sss
Vladislav Grishenko aka theMIROn
Ekaterina Gritsenko aka Tuarisa
George Hazan aka ghazan
Alexander Lantsev aka Unsane
Franz Leecher aka leecher
Nikolai Romanovich aka MikalaiR
Ivan Rozhuk aka rozhuk
Alexander Shorin aka Kxepal
Matej Som aka zemiacsik
Kirill Volinsky aka Mataes
Tobias Weimer aka Wishmaster
Leonid Yuriev aka ly

Sound pack is developed by Andre Louis aka onj

People that previously used to develop Miranda IM/NG Project:

Robert Pösel aka Robyer
Alexey Koulakov aka Awkward
Bartosz Białek aka Dezeath
Michael Kunz aka Protogenes
Dmitry Kuzkin aka Bio
Eugene Lishnevsky aka elishnevsky
Vlad Mironov aka mironych
Victor Pavlychko aka nullbie
Konstantin Romanov aka Kildor
Artem Shpynov aka FYR
Alexey Oblezov aka faith_healer
Ulrich Hecht aka fishbone
Vitaly Igonin aka persei
Vadim Dashevsky aka watcher
Ricardo Domenecci aka pescuma
Gennady Feldman aka gena01
Martin Öberg aka Strickz
Denis Stanishevskiy aka std
Richard Hughes aka Cyreve
Santithorn Bunchua aka keh
Sam Kothari aka egoDust
Jörgen Persson aka Matrix
Tim Hunter aka cojones
Kubilay Kocak aka koobs
Boris Krasnovskiy aka borkra
Josef Kucera aka joe_whale
Aaron Landwehr aka snaphat
Lyon Lim aka lyon
Tjado Maecke aka tjado
Piotr Piastucki aka the_leech
Robert Rainwater aka rainwater
Alex Sanda aka Nightwish
Adam Strzelecki aka OnO
Maxim Mluhov aka mlu
Scott Ellis aka sje
Cristian Libotean aka eblis
Roland Rabien aka FigBug
Tristan van der Velde aka Tristan_VdV 
Emostar
Esnow
Crypt0gl
Lowspirit
Glutnix