[simonw]

It's a mistake to lump jQuery in with Prototype and MooTools as "doing things significantly differently and only sorta playing nice with each other". jQuery very deliberately avoids modifying built-in objects to ensure compatibility with other libraries and existing code.

[ericwaller]

I'm not sure why this comment was down-modded. You may disagree with the first point, and it's certainly subjective (whether or not grouping the 3 is a mistake), but the second point is 100% correct -- it's one of jQuery's primary goals.

http://docs.jquery.com/Using_jQuery_with_Other_Libraries

[KirinDave]

Except that it's really not any better. In any case you're going to have to have another library doing the same damn thing with its own instantiation and calling conventions.

Just because it doesn't deliberately destroy compatiblity doesn't mean that it's really helping the problem.