I really like the new Yahoo design, more so than the extra space I think.
As per Gmail scanning your email, I have a Gmail account, and I do like it. It just as some very un-intrusive ad's on the side. The way that messages are scanned to give you the ad's on the side are the same way that spam filters work, by scanning your email. These ad's are only text, so they aren't nearly as bad as the photo ad's that you get on MSN
/Hotmail with are very intrusive, or the ones on Yahoo, which are slightly less intrusive.
I liek Gmail's system so that you can have conversations, and the quick reply feature, etc.
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