Let me see if I can summarize the games adequately.
BioShock is, as previously mentioned, a story-based FPS (in other words, no multiplayer, so all the Halo kids will hate it) from the guys who made the System Shock games. You're trapped in an underwater city created by a splinter of society who broke off to create the underwater paradise based on the ideals of Ayn Rand. I think it's supposed to be more of a criticism of her works rather than a homage, actually. Anyway, these guys discover this stuff they call 'adam' while living underwater that humans can use to genetically modify themselves, but sometime afterwards something goes horribly wrong and the player is sent down to investigate it. The crazy stuff about the game is that as you collect this adam in different ways you can genetically modify yourself in a sort of RPG-skill-tree way. You can get telekinesis (as you can see in the YouTube video where he picks up the oil drum and chucks it at the dude), you can learn how to hack the computer systems of the city and use the security robots against the dudes you're trying to fight, you can make yourself super resilient to bullets, and so on. Basically it's a fantastic-looking game that also gives you about a billion ways to customize your characters and kill dudes, with a compelling story to boot. One of the major moral issues in the game is that you can harvest by far the most adam by killing these things called 'little sisters', which for all intents and purposes look and behave like 9-year-old girls.
Mass Effect, on the other hand, is being made by BioWare and published by Microsoft (so there's no way this one's going to the PS3
ever), and it's an action-RPG set in 2183. You're a diplomat/investigator (part of an interplanetary organization known as the Specters) by the name of Commander Shepard, and you travel around the galaxy keeping the peace in numerous ways and you uncover a conspiracy surrounding a massive alien fleet that's preparing for war. The idea is that the game will have a fantastically deep conversation system (because you're a diplomat), where you can alter the entire course of the game simply by how you approach certain people during the storyline. It might not seem like a great feature to tout, but basically the story can change massively if you threaten some random alien bartender instead of negotiating with him calmly or bribing him or whatever other options you have. It's going to be similar to KOTOR and the Baldur's Gate games in that the combat will take place in real time but you can pause at any point to give your character and the others in your party directions.
These descriptions might not sound like anything particularly groundbreaking, but critical reaction for both of these games so far has been
overwhelmingly positive. I read a particularly gushing article for Mass Effect in Game Informer a week or so ago; it basically said that it's setting the bar that RPGs will have to live up to a decade from now.
EDIT: Also, Gamespot's review of Shadowrun is
up. I guess there's a reason Microsoft wasn't shipping it to press outlets on time.