As someone who can't afford to upgrade due to the fact that operating system cost way more than I can afford, I hope The Sims 4 will run on Windows 7 just as much as The Sims 3 can run on XP and Vista.

I have a high-end computer that can run circle around my old computer, Bessie, who only have 100GB of space. Joelle, my most recent computer has 1TB of space.

Then again, I'm not upgrading because I'm trying to keep my other Sims games (both 1 and 2 are also installed.)

There's no reason why it won't run on Windows 7

This is a bit off-topic, but Is you're computer's name, Bessie by any chance a reference to the Third Doctor's car from Doctor Who?

When EA actually releases the game, they will tell you what the system requirements are. Assume that things at the low end of the range won't run the game well.

Actually, I called my computer Bessie as she was a workhorse for writing much akin to the street paving machine Bessie from Disney\PIXAR's "Cars 1"
She was slightly slow and buggy for a computer during late 2011\early 2012 (which was when I got Joelle)

I guess the patriarchal tradition of naming machinery after woman is a holdover from a bygone era, but the reason I as a woman chose to name my machines after women was based partially on a gender stereotype experiment done by the MythBusters.
In that test, the men failed miserably, always doing things one at a time where as the women successfully made lunches for work and school, got dressed, made breakfast, answered the phone and kept a baby robot (dubbed Buster Jr.) from crawling out the door.

Why yes of course.

It most likely will work even on XP.

If the OS is popular, it will likely be supported.

Also, since almost nothing in terms of code is different on 8 than vista or 7, expect it to work unless they use the newest direct X, which is not compatible with XP, Vista or 7.

If they do that, you will be forced to upgrade.

Don't worry about it supporting 7. If one won't be supported my bet would be on XP since it's past it's life cycle and not supported by Microsoft anymore. That's a big if though because many people still have it. My biggest fear about the system spec's would be it not fully utilizing 64bit personally.