I like the simplicity of Safari on OS X. But, there are some sites, like CCBill and Mint.com, that I need to run on FireFox.

There was a Java update 3 weeks ago, followed by a Safari update, and there have been some noticeable changes in mouse point-and-click actions ever since.

Especially if I have hit a page with lots of CSS, my mouse actions change, e.g. single-click insertion of cursor at a certain location, double-clicking, triple-clicking, select-drag-copy.

There is coming a point where CSS needs to slow down to take into consideration the limitations of the hardware and software that it must coexist with.