Growing up through elementary and middle school with a serious hatred for writing papers, like everyone else my first resource was wikipedia. Even though we had presentations by the librarian about how much they hated wikipedia, and how you cannot trust anything, I would still use it, all the time, but why? Because of sheer convenience. Also, I never bought into the idea of "anyone can post anything they want, so you cant trust it", I feel that someone would have to be either really bored and really strange to completely make up almost a whole page about the war of 1812 with very detailed dates and info. The type of person that gives that information about the war of 1812 to wikipedia is obviously an enthusiast and most likely knows their stuff, so bassically its a great starting point. Plus, any real "prank" entries get resolved almost as quick as they are posted...
10 years from now, I feel wikipedia is just going to grow an expand its wealth of information and any competitors will most likely be non existent. However, I do feel enyclopedia brittanica will still be around, but I think they will start focusing more on their other options that wikipedia currently does not have, like access to magazine articles, ebooks, and primary sources.