Its not Metal Gear Solid, and that's not a bad thing. Acid has a lot to offer and is perfectly suited for handheld.
Metal Gear Acid is not Metal Gear console. It's turn based. It's card based. At a glance, neither of those elements seems like it has any business anywhere near the Metal Gear franchise. After having spent some time with the Acid though, all I can say is that it really works. As strange as it may be, I'd rather have this version of Metal Gear on my psp than a console version. The card strategy lends itself to some intense moments, which really is odd considering you're just taking turns. There is still that feeling you get when you sneak up behind a guard and snap his neck. It feels like Metal Gear, but it's Acid, and that's an awesome thing that they pulled off.
The game is broken up into short missions with in the larger story, which is ideal when most hand-held time is spent in short sections on buses, on the toilet, etc.. They're is a myriad of videos and cards and arena battles to unlock, so there's always something new. I haven't had an opportunity to try the multiplayer, but I can see how pitting your deck against a friends would be fun.
Graphics are spectacular acrossed the board. From the cell shaded character models to the very enjoyable animations and effects, it all just works, and works well.
They story isn't bad. Cut scenes would have been nice, but the artwork is interesting enough that it's not a big deal.
They solid eye 3d attachments works. It's hard to use it for more than 5 or 10 minutes at a clip, but it is cool to be able to watch snake blow away a boss in full on 3d. The solid eye theater is also very cool, although the videos of the Japanese girls parading around was not necessary to say the least.
Overall, if you're a fan of the Metal Gear series, and enjoy strategy at all, this is a very enjoyable and addictive play through. I'm hooked.