The best/most informative site I've found for stroller info is Baby-Gaga. They've combined field research with parents' reviews to come up with a thorough discussion of each type of stroller. Go direct to their comprehensive single stroller reviews or double stroller reviews and start browsing (each name is clickable to an easy-to-read, multi-page review), or narrow the list by a variety of criteria on the left side.
We're going with the Graco DuoRider for quick daily trips like groceries, mall rat visits, trips to grandmas, etc. Then we're going with the Baby Jogger City Double for anything where we'll be covering a lot of territory or outside. I'm in love with this Baby Jogger City Double after test driving it yesterday, and would use it for my daily stroller, but it's way too heavy for me to lift in and out of the car on a regular basis.
This online info isn't a substitute for test driving the strollers yourself, by the way. TubaDad and I went to a baby store and drove every single double stroller. You find out real fast what you can't stand and what makes your eyes light up. In my case, most of the standard side-by-side double strollers have a third set of wheels in the back that I kick as I walk. Very annoying with tennis shoes on, and probably painful with sandals on. (I'm 5'7", so not an amazon or anything.) We also took the strollers out to the parking lot and I practiced folding them up and getting them into the back of the car. Huh - it's wayyy harder than just collapsing them and opening them back up in the quiet, clean, air-conditioned store aisle.
Final note: if you have a little time you can get some great deals! Your local stores will always offer seasonal sales and can tell you when they're coming up, or you can find any stroller online with free shipping, or (for the big-ticket items like the Baby Jogger) hop on over to Ebay and look for some incredibly-competitive pricing from sellers with sterling reputations.