Pablo, lots of good advice in this thread so far- it interests me too, because my little Fuji 3.2MP that was such a screaming bargain a few years ago seems badly dated now. It still looks great & works perfectly, but we all want a new toy now & then, huh?
The more I look at these things, the more I keep coming back to Canon & Nikon. Mori's suggestion of going for 28mm equivalant on the short end of the zoom- well, let's just say that's fairly rare and will greatly reduce your choices. It *is* absolutely one of the best features you could have though. Easily worth the camera's weight in gold when taking group shots during the holidays!
Having said that- 35mm equiv on the short end is still pretty good. Just don't get carried away worrying about the long end of the optical zoom, anything near 100mm equiv makes a nice portrait length & is all you need- in fact ~70-75mm is long enough, IMO. You won't find many of those though.
Viewfinder: Again, Mori's dead on. Viewfinders are rapidly disappearing, fewer & fewer new models have them. From my personal experience, I'd absolutely insist on an optical viewfinder. For all the reasons Mori stated, *plus* the fact that some cameras(like my old Fuji) allow you to keep the rear screen switched off if you like, which will greatly extend battery life in real world usage.
If I was gonna buy one right now, I'd look awfully hard at that sweet little black Nikon mori showed above. Suck it up, spend the extra $100, & every time you use that nice true wide-angle focal length you'll pat yourself on the back.
Or for only $50 more than you'd originally planned, Walmart has a nice little Canon PowerShot A560 on sale now for $150. 35-140mm equiv zoom lens, 2.5" rear screen, face recognition, image stabilization, red-eye correction, and *drum roll*: an honest to goodness optical viewfinder! Uses SD-MMC memory cards(the overall winner of the memory card wars, now offers the most memory/$, 2GB available from Buy.com for $13.95 shipped) & AA batteries too. Small enough to take everywhere, but has the grip-shape on the RH side that makes it much easier to handle & use than the cute little deck-of-cards models. Sure looks like a lot of compact camera for $150 to me.
Just remember that models & deals change all the time, & when making the final choice there's no substitute for actually getting your hands on it. Good hunting, & let us know what you get.