Oh, you meant the userpic! Why didn't you say so in the first place? :p

As far as I can tell, the "e" is just as you observe. The "i" (looking at a larger version) appears to be dotted with a mandala, presumably for Hinduism and/or Buddhism.

(I saw another version earlier where the "e" had =mc^2 under it, but it wouldn't resize legibly.)