Well finally, someone left behind a copy of Resident Evil 5 for me to rent.
My thoughts so far: I like it. It plays just like RE4, except you're not alone, the graphics are improved, and you can strafe! Well, you can't run and strafe, you can only sidestep slowly, but it's better than nothing.
The inventory system is a step forward, and a step backwards. Everything occurs in real time now, which actually ups the tension. You can't do like in RE4 and hit the pause button, heal yourself, and switch to another weapon without having to reload. You can still change your weapon on the fly, but it's in real time now. However, you can't hold as much stuff as in RE4. The size of your items is no longer an issue, for the inventory is like the older games, a 'box' for each weapon, healing item, and ammo. Key treasures are still separate, thankfully. But I liked the inventory system in RE4 more, and not just because it could let you cheat.
Aside from that one concession, it's really good. Buying and selling stuff is easier now, since you can do that anytime you load a saved game. Saving is automatic now, like in most shooter games.
Of course, some things are still the same. The controls are nearly the same. The "zombies" are nearly the same, (although you get to frag African tribesman zombies in this game, as opposed to zombiefied religious zealots like in RE4) most of the weapons are the same. The story is still average, (oh! Someone getting away with bioterrorism yet again! Whatever will we do!?) the voiceovers are still average, (but hey, anything to not suffer the PS1 RE games' voices ever again.) the only interesting character is still Wesker, the recurring villain.
If you liked RE4, you should like RE5.