Resident Evil 5 was notable for me because I played it shortly after playing Prince of Persia next-gen, so the contrast between the friendly AI in those games pretty much caused me to create a new category system for such AI:
"Elika" characters - these AI teammates do what they're told; go where they're instructed; and only act when you tell them to act or if you actually need help. Best of all, you never have to babysit them and when they do involve themselves in your experience they're genuinely helpful.
"Sheva" characters - these AI teammates do whatever the hell they feel like when you're running around with them. They'll run right into a pack of enemies; intentionally suck away your ammo and health items (even going so far as to go for them before you can); refuse to run from said pack of enemies when they get surrounded; and when they go down YOU go down. Rarely helpful, you spend most of the game babysitting them and having to jump through a great number of hoops just to make sure they don't ruin your experience.
Mere words can't express my outright hatred for the Sheva AI in RE5, as she's obnoxious; useless (save for like 2 levels where her pinpoint computer aiming is handy); and adds absolutely nothing to the game. As for the game itself, "meh". There are some incredible boss fights (taking out a giant leech-like monster with the GDI Ion Cannon for the win!) and cinematic moments, but especially after playing Dead Space the game feels very clunky and honestly not very much fun to play (IMO, of course). They took away a lot of the stuff that made RE4 fun, such as the merchant (really, they could think of no reason for an illicit arms dealer to be in Africa?); being able to hunt down treasures and combine them with other treasures for greater reward (yeah, the treasures are still there, but they exist for no other reason than to be immediately sold); inventory management via the upgradeable (and, for a Resident Evil game, realistic) attache case system; etc. The plot is nebulous and not particularly interesting to follow till very late in the game, and the end boss despite being "epic" drags on for way too long and ends in what even for a Resident Evil game should be a ludicrous boss environment.
I liked RE5, but upon completing it once I felt satisfied. I didn't get that feeling of immediacy I had with RE4 where I had to replay it again right now. It also isn't scary in the least, despite bringing back some of the better beasts in the RE franchise (though surprisingly not the regenerators from RE4). And the reviews weren't lying on this point: I completed the game using only the computer AI Sheva, and it was painful. Do whatever it takes to play this game with an actual human being.
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ADDENDUM: RE - S-E support on Wii - Yeah, I would consider SE putting the next "real" Final Fantasy on Wii as a sign of real support for the system, but we have to accept the facts on this: Square is never, ever going to put another mainline Final Fantasy game on a Nintendo system, because Nintendo doesn't produce consoles with the technical firepower Square wants...not anymore, anyway. No, that's pie-in-the-sky, and will only happen if there's a major and unlikely shift in the industry and we lose one or both of the other major console manufacturers.
What would satisfy me is if S-E brought back true sequels to some of their lesser franchises or ones that would suit the console to Nintendo, not wacky FF spin-offs that have little to do with how FF games usually play. What about Kingdom Hearts 3? It has never made sense to me that S-E never brought the Kingdom Hearts games to the GameCube, as it could have certainly handled them. I also think that Kingdom Hearts 2 still looks pretty good for its age, so I don't think that the Kingdom Hearts games would benefit as much from the "HD Experience" as something like FF. It's perfectly do-able. S-E has so many properties under its command that I find it impossible to believe that none of them save some Final Fantasy spin-offs could make its way to Wii.