Cross-platform, cross-browser Javascript profiling performance

Question

In addition to my recent question on profiling a PHP application on the server side, an application can have a ton of javascript, being all AJAXy in content.

This raises the question of cross-platform, cross-browser javascript profiling tools: do they exist, what kind of people do they use and what are the benefits for each of them?

Great importance.

Answer 1

http://testswarm.com/

Answer 2

you can do profiling in firebug, don't know about the chrome console, although

Answer 3

HTML 5 Boilerplate.

Javascript, IE6/7. , . , -/.

Answer 4

, - JavaScript , , , , .