Some people believe that jQuery and MooTools are direct competitors. This a big misunderstanding!
MooTools provides many many modules. Most of them are optional. Some of them depend on others. If you want to use some bits of MooTools for some things and jQuery instead of MooTools Element module or Request modules, you can easily create a custom build of MooTools with only the bits you want. Moo4Q.com is a cool project that makes working with both a lot easier. There are a ton of things in the Forge and in More that require the MooTools Element module and not jQuery. Those obviously won't work unless you include the right stuff in your build. On the other hand, there are a ton of things in the JavaScript ecosystem that require jQuery for DOM manipulation and not MooTools Element module. But you can still use tons of awesome MooTools stuff even if you choose not to use the Element module. The jQuery and MooTools guys have all done a lot of great stuff! Don't feel bad of you want to use it ;) It's all just JavaScript. — Thomas Aylott - SubtleGradient - MooTools - Sencha (from iPhone 4)
