When you receive a message on a chat window you already have open the tab for it should blink, like AIM does.
When you are matched into a game the PvP.net tab should blink.
Also on the champion select page, the transitions between tabs are really slow. I find it annoying when I try to change my runes/spells at the last second.
Lastly, there should be a chat room that is automatically created for an arranged team while it is waiting to be matched.
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