The changes in MAME 0.84 are ALOT so if you need to read them all just read the changelog in the archive you are about to download. In the meantime here are the changes that have to do with games:
New Games supported or promoted from GAME_NOT_WORKING status:
Hangman [Pierpaolo Prazzoli]
Dragon Bowl [Pierpaolo Prazzoli]
Knightmare (prototype) [Pierpaolo Prazzoli]
Many new sets of Grayhound Trivia [Pierpaolo Prazzoli]
Psychic Force EX [smf]
Double Point [David Haywood]
New Clones supported or promoted from GAME_NOT_WORKING status:
Puchi Carat (World) [Brian Troha]
Dragon World II (ver. 110X, Export) [David Haywood]
Vapor TRX (prototype) [Aaron Giles]
Street Drivin' (prototype) [Aaron Giles]
Empire City: 1931 (US) [David Haywood]
Final Blow (US) [David Haywood]
Gold Medalist (alt) [Pierpaolo Prazzoli]
Saboten Bombers (set 2) [David Haywood]
Mega Zone (3 alternate sets) [David Haywood]
Street Fight [David Haywood]
Fantasy Land (set 2) [MASH]
New Non-Working games / clones supported:
Idol Janshi Su-Chi-Pi Special [Pierpaolo Prazzoli]
The Killing Blade [David Haywood]
Squash (Ver. 1.0) [Pierpaolo Prazzoli]
Thunder Hoop [Pierpaolo Prazzoli]
Pocket Gal Deluxe [David Haywood]
Diet Go Go [David Haywood]
Double Wings [David Haywood]
Boogie Wings [David Haywood]
Osman [David Haywood]
Chain Reaction [David Haywood]
Magical Drop [David Haywood]
Magical Drop Plus [David Haywood]
Charlie Ninja [David Haywood]
Joe & Mac Returns [David Haywood]
Ganbare! Gonta!! 2 [David Haywood]
Heavy Smash [David Haywood]
World Cup Volley '95 [David Haywood]
Backfire! [David Haywood]
Space Lords (2 new sets) [Aaron Giles]
Moto Frenzy (3 new sets) [Aaron Giles]
BMC Bowling [David Haywood]
Meijinsen [David Haywood]
Mahjong Block Jongbou (Japan) [Pierpaolo Prazzoli]
Gals Panic 3 [David Haywood, Sebastien Volpe]
Tornado (2 sets) [David Haywood]
Street Fighter Alpha: Warriors' Dreams (Euro 950605) [Razoola]
Street Fighter Zero 2 (Oceania 960229) [Razoola]
Marvel Vs. Capcom: Clash of Super Heroes (Brazil 980123) [Razoola]
Street Fighter Alpha 3 (Brazil 980629) [Razoola]
You can get MAME & MAME32 from here.
