I build this
website which is supposed to run on the iPad (it does) and in Google Chrome. In Chrome (on Win 7 64bit), after a seemingly random time of a few minutes, the browser freezes. Also, sometimes when I click the "Reload Page" button in Chrome while on this site, the Browser also freezes. In both cases, the Browser recovers after 10-20 seconds.
I really doubt it is your script; rather, I think it is Chrome doing something silly. I would test it on other similar systems to see if you can reproduce it. I've had it running on mine for about 5 minutes with no issues (Win7, 64bit, Chrome 5.0.375.127).
You could try to keep the profiler running and catch the freeze-up, but I think that would just be a waste of time.