Ok here we go:

1. Tabbed Interface
   It's really annoying that you can't go back and look at other messages while a) keeping the message you are viewing open or b) composing a new message. If there was just the *option* of having new messages open in a tab-style thing inside GMail it would make it so much better!

2. Multiple Signatures
   This one just seems retarded to me. I can send and receive from multiple addresses, even use my own server to send, but can I have a different signature for each address I send from? No way! (and using Firefox or Chrome add ones to do this is not cool as they are not on multiple computers and can't be on my iPhone and they are extremely unreliable (i'm looking at you Wise-Stamp/Blank Canvas).

3. Send From Different Addresses From the iPhone
   When I'm on Gmail (the web version not using the native mail client) it would make sense if you could select which address I would like to send from (and those signatures would sure be handy there too!).

4. GReader-Style Expand Collapse In Message View
   So when you're viewing a long message thread and a whole bunch of messages are in the collapsed view it would be great if you could just click "j" or "k" to go through the messages in the thread expanding/selecting them in turn.

5. Short-Cut ReMap
   This is a nerdy one but I really like keyboard shortcuts. Why does GMail have it's own random shortcut (tab+enter) to send mail when every other mail client on teh planet (including the web interface for Yahoo! Mail) uses Command/Ctrl+enter. It just doesn't make any sense! I wish you could just re map things to whatever you like.

Ok so what did you think? Surely it's not just me that would have like the hours and hours of development time poured in to buzz poured in to stuff like this instead right! If they were gonna force a crazy new feature set on us at least it could have been something that really benefited Gmail users!! Even if they just put these features in Labs.

Phew. Ok. Rant Over.