UPDATE: As of Monday morning I was able to re-upload my profile pic. However, some users still have issues.
Twitter is having problems uploading profile pics for various users. I’ve fallen victim, of course, as you can tell by the little “birdie” icon next to my Twitter status. I never checked their site before attempting to upload a different pic – then again, I wouldn’t expect there to be any issues.
Information on the problem is posted at Twitter’s site. Though they reported that the issue was mainly fixed, hundreds of people are still reporting problems.
I’ll update here when new info is available. For now, leave your profile (and background) images alone.