$ itself is a god object. Everything goes on it. The standard plugin / extension architecture that is recommended is to just bolt more methods on $ itself!
Surely this is bad. An example would be how we have both $.load which is overloaded to do completely different things. If they were on two separate sensibly named objects $Container.load and $EventTarget.load. Personally I would deprecate the latter in favour of .on('load'
The animation should be it's own little modular thing, not bolted onto $. Ajax should be it's own little modular thing, not bolted onto $