I tried out the new Twitter Header image thingy yesterday and gave it a C+/B-. It looks like we are stuck with a white text overlay on your photo so be sure to choose a photo that is dark or nobody will be able to read your bio.
Still, it’s worth spending some time designing up a header image (Learn how here).
I randomly collected some new Twitter Header images I saw this morning. Mention yours to me on Twitter and I’ll include it here, too.