Game type: Simulation (like, duh)
Time demand: You can save whenever... if you, y'know, don't lose track of time and get completely absorbed. Or something. Not that I have any reason to mention that, nope, nossir....
Platform: Nintendo PC/Mac
Released: June 2, 2009
What it is: Alright, for those of you who've never played a Sims game... first... *picks up rock, heaves it out of way*
Sorry, sorry. *ahem* anyhow. In the short version, you can create your own Sim(s), single or family, or roommates, or whatever. (Up to 8 can live in a household.) Or you can just choose to play one of the pre-made Sims that came with the game. Then... you play out their lives. Voila!
Okay, to go into a little more detail. There are various meters (hunger, bladder, social, fun, etc.) that a Sim needs or wants to keep as full as possible. Some like hunger will kill a Sim if you let them run out, others will just mean that the Sim won't want to do anything really until the need is met, or performs badly at work, etc. There are also "moodlets" that you pick up from doing various things (lots of garbage lying around adds negative moodlets, doing something fun for long enough at a stretch adds a positive one, etc... and trust me, there are TONS of these). The fullness of the various meters and the modifiers from the moodlets combine to make your Sim's overall mood, which helps affect how they perform at work or school, what they're willing to do, etc.
You can build your Sim's house, buy them things, buy groceries and new books, etc etc., but of course this takes money. And to get money... you (mostly) need a job. There are a handful of different careers around town that you can apply for, and you work certain hours on certain days, pulling down an hourly salary. Sorta... just like real life. :p If you meet certain requirements, you can be promoted, get raises, etc. Perform badly enough (go to work in a bad mood too often, be late for work/skip work too much, etc), you can be demoted, or even get fired. You can also make money though buy growing fruits and vegetables in the garden and selling them, catching and selling fish, writing books and pulling in the royalties, etc etc. Basically, there's a ton of different things to try and do.
Your Sims can build relationships, fall in love, get married, and adopt/have children, raise families, etc. Sim children go to school, have curfews, can't live on their own, build up their skills for later in life, and so on. Once they grow old enough, they can continue to live at home, or you can move them out (and lose direct control over them... or switch direct control from your current family to that Sim's new household, or whatever). The neighborhood continues to grow and evolve via the AI, as you control your own little Sim family, although you can switch between active families if you like. (It's just a bit of a pain).
There are other things as well... lifestyle points that you get from fulfilling wishes that your Sims have, Lifetime Wishes that you strive to meet, and so on. But this should at least give you a general idea of what the game is - keeping in mind there's a *ton* of stuff to do, that I haven't gone into because there's just not room. You can go fishing, go to the park and play your guitar for tips, wander around town and meet/hang out with your neighbors, search the galaxy for new stars (and possibly spot a meteorite as it falls), collect rocks and insects, have a picnic, play custom radio stations on the in-game radio to have songs from your actual music collection during the game... and on and on and on.
I'll probably do another post soonish, comparing the Sims 3 with Sims 2, for those who *have* played Sims 2 and want to know how they compare. But this is already long enough, and I want to get back to the game. ;)
So if you have something you want to know - either because you haven't played and I didn't give enough detail, or if there's something specific you want to know about changes/developments/etc., note it in comments, naturally.
Recommendation: Fun and addicting. Seriously. And quite a nice evolution from Sims 2 for those who have played that game... with unfortunately a few wrinkles to iron out still. But still worth picking up.