I think this is due to a trailing comma in a list. Real browser are OK with it, but IE is dumb.
Seeing this issue seems to be a bit hit and miss, I haven't worked out the combination of parameters that causes it, just that sometimes it'll happen and sometimes it won't (even with the same browser.) I suspect it's to do with the order that certain ajax loads take place relative to JS rendering.
Created attachment 11251 [details] [review] Bug 8547 - JS error in star ratings breaks IE Writing code with best practices in mind breaks IE. Thanks Internet Explorer. Now go DiaF.
This patch is based on a hunch of what the issue is and is still waiting for someone who has IE to test it for me, but if anyone else is interested, here's what it looks like when it's going bad: http://i.imgur.com/Jhc3z.jpg
For what it's worth, I don't see this problem in IE9 on Windows 7.
I was testing IE 8 on Windows 7 and saw it sometimes. Most of the time it happened after closing the browser completely and going to the detail page directly following a link from my bookmarks.
Confirmed from client that this solves the issue.
Bug confirmeed with IE 7.0.5730.13 on Windows XP
Created attachment 11361 [details] [review] [SIGNED-OFF] Bug 8547 - JS error in star ratings breaks IE Writing code with best practices in mind breaks IE. Thanks Internet Explorer. Now go DiaF. Signed-off-by: Marc Veron <veron@veron.ch> Tested with with IE 7.0.5730.13 on Windows XP, no JS errors, stars display and behave as expected
QA Comments: This patch fixes a "Trailing comma of death" (see http://www.enterprisedojo.com/2010/12/19/beware-the-trailing-comma-of-death/) for IE Passed QA
Have picked this into 3.8.x, will be in 3.8.4, safe change, fixes broken IE. (Well fixes one small symptom of its huge pile of brokenness anyway) Leaving as Passed QA, so Paul can push to master when he gets back.
Patch pushed today (checked it does not break FF)