Summary
Dramatically improves upon the original, but loses quite a bit in the way...
The Good
The Legacy of Kain series is probably one of the best 3d action/adventure franchises out there, which carved a name for itself by adding some innovative touches to what's essentially a stagnant formula but also by adding to the gameplay an incredibly solid storyline and setting, which continues to twist and bend in every direction in this new sequel.
I won't bore you with the details of what made Soul Reaver 1 so good (just check out any of the reviews), but instead allow me to do a quick rundown as I mention the areas where the game has improved:
The gameplay remains basically the same, which is a good thing. The game thrusts you into what's more or less a seamless world through which your character goes around unearthing the story and gaining new abilities. These abilities unlock new areas of the world and the cycle repeats itself again and again. On top of that, time travel now takes you to different ages of the same location, which unlocks even more challenges and so on. As before, you can switch between reality planes in real time, suck souls and battle re-spawning enemies as you solve puzzles. Said puzzles have been extremely improved and now provide original challenges that call for Raziel to make use of all his abilities and think a bit instead of pushing boxes ad infinitum (the annoying box-pushing puzzles from the original are in fact, gone). Combat has been considerably improved, with a new "lock-on" feature (seen also in other games of this type) that allows you to easily circle-strafe around an enemy, dodge, block and parry his attacks besides just slashing randomly in his/her direction.
The story in the original Soul Reaver was a surprising delight of treachery and plot-twists, and this time things are taken even further. Having had his revenge, Raziel now travels in time in pursuit of Kain, but this little adventure faces him with some unexpected revelations, such as his own true nature and how both him and Kain were fooled by other forces. Additionally, the time travel element takes you in and out of several key moments in the history of Nosgoth, and it's truly a magnificent sight to see how well the writers managed to make seemingly paradox-inducing elements work for them and thus deliniate the fate of Nosgoth as well as give hope to it. Raziel for instance, is found to be the cause of his own doom, yet he finds out he's the only one with the power to alter fate. Those as well as many other plot-points once again weave a web of conspiracy and treachery that will leave you dizzy before you know it. Luckily, this time around the developers included a diary that keeps tabs of every conversation and event in the game for easy review.
Finally, as befitting a next-generation game, Soul Reaver 2 sports some of the most impressive production values in it's class, which include SPECTACULAR voice acting and musical score as in the original, as well as truly amazing graphics that make the original look like a Gameboy game with a completely re-done engine, new models with larger poly counts, larger stages with more detailed texture work and all sort of lighting and particle special effects for some excellent eye candy.
The Bad
It's even shorter than Max Payne! And that's saying something... Not only is the game shorter than the original (by a lot!), but it's completely linear with all the optional glyph quests removed and leaving you nothing to explore on your own. To top that off it's incredibly easy! Save for some rather nasty plane-shifting monsters that appear in some of the later time-eras, each and every fight in the game is a doozer. Gone are the puzzle boss-fights from the original, replaced with the same generic bozos you can eliminate with a couple of hits... it's a shame really as one can't help but wonder why they improved the combat system so much only to have virtually no challenging fights in the game!
Additionally, there's a particularly infuriating problem with the PC version, and it's the fact that while the original PS2 Soul Reaver 2 was just as short, it featured an entire DVD-worth of extra materials to complement this. When you finish the PS2 version you get a code and this unlocks a pletora of extra features which include a veritable roadmap of the Nosgoth continuity (complete with a detailed timeline), cutscene collections from the original Soul Reaver as well as Blood Omen, and a wealth of behind-the-scenes material showcasing the making of Soul Reaver 2.... The way I see it this omission is a clear "Fuck You!" to PC gamers, and I'm not taking it lightly.
Finally the game ends on yet another cliffhanger wide-open ending, basically saying a lot but resolving nothing... So far the series is interesting enough to arouse my interest, but if they keep pulling this trick I'm not gonna be around it for much longer.
The Bottom Line
Soul Reaver 2 improves upon the original in practically every way possible, taking the already fantastic gameplay and content to new levels of quality. Unfortunately in the way it also found a way to lose enough length, challenge and non-linearity so as to coming really close to being an interactive movie... This is something to take into consideration from a gameplay-value point of view, and also if they expect you to pay anything above 10 bucks for it.
Finally (and I HATE saying this) get the PS2 version as it packs all the extras that made up for the lackluster value in the game.