Gran Turismo 2? I'm assuming GT6 doesn't count since it is the latest entry.

The game's release had a pretty shitty timing, so it's no wonder. I don't know what Sony/Polyphony were thinking.

So it's finally time for me to join this thread... I'm way behind, but here's a dump of some hints.  I'll try and guess some other people's if I get chance too!

#50 - Arcade port, first game in a franchise which released with the launch of every single console from one of the big three... until last year. (guessed by artur-fernand)

#49 - The previous game fully established open-world as a mass-market thing; the sequel ran with the idea and blasted it into the most fantastic setting imaginable, with a killer licenced soundtrack. (guessed by artur-fernand)

#48 - Prior to creating this open-world adventure starring an amnesiac girl, the development "studio" had worked exclusively on a horror franchise for more than 5 years. (guessed by soulfly666)

#47 - (this'll be a tricky one).  Long running "racing game" series which received a duff entry on the PS2 only to be revived on the PSP.  This is the entry that followed that PSP rebirth. (guessed by artur-fernand)

#46 - Released as a 10th anniversary celebration of this JRPG series, the 5th numbered entry and currently last entry in the series (not counting a spin-off)

#45 - Kitty Kibble shortages and broccoli everywhere.

#44 - A game featuring the original bastards - one who told you off for quitting without saving; the other a massive money-grabbing twat.  This was the original that was tile-based, unlike its successors. (guessed by Wright)

#43 - After swapping green lands for a murky city, this second sequel traded both of the above in for the desert.  Featured a "wizard of oz" esque ending.

#42 - First person platformer starring a robotic rabbit.  There can only be one. (guessed by soulfly666)

#41 - The final boss of this fighting game was a young woman who beared a startling resemblance to a missing character... who had been possessed by a phantom spectral wolf.

#40 - Hands down the best Star Wars game ever made; the sub-series is finally being revived soon. (guessed by artur-fernand)

#50: Riiiiiiidge Racer. This joke was old in 2007, forgive me.

#49: GTA Vice City

#43: Uncharted 3? Never watched Wizard of Oz, so I don't know what that's about

#40: Battlefront 2

And here's my #40 hint, a lot people missed it apparently: A bit hotter. A bit cooler.

Yep on 50, 49 & 40; nope on 43.

I'm impressed you knew to guess Battlefront 2 and not Battlefront 1, as well :P

Didn't know your clue I'm afraid, sorry!

Animal Crossing?

After the sequel came out, not a whole lot of people care about the first one apparently.

Also, is #46 Suikoden V?

Wright!

No, but surprisingly, after researching it this seems to exactly fit the description too :P

You're on the right lines.

Fire 'N Ice?

Would be rare though .

I honestly can't think of any other rpg series that fits the description. But I thought of some of your other games:

#48 is Siren?

#47 is Wipeout Pure? (or Pulse... or maybe HD)