You guys know the little red icon that sits next to your username and lights up whenever you've got updates? I looked at the unread icon when it was lit up and immediately thought of gmail, so then I looked at the gmail icon (especially the favicon) and the two look exactly alike. They look even more alike when the unread icon is lit up and red like the gmail icon.
I was just worried that their might be some sort of legal issue with this. On a different note, I don't really like it because it just makes me think of Gmail. If you made the "M" shaped lines not extra bold it would look perfect.