Hmmmm, I'm not sitting with the exact details in front of me at the moment, however let me try to qualify my dislike of some of GMails features, and even to compare against Yahoo (which I shelled out $29 for).
GMail ...
- 2gb Mail Limit
- Scans your messages (by script) seeking to throw an Ad (popup or embedded, it is unknown at this point)
- Web Based Interface
Yahoo ...
- 1 gb Mail Limit overall, 25mb per message for attachments.
- Scans your messages (by script) seeking to reduce the spam in your mailbox. Files found spam messages under BULK.
- Web Based Interface, along with POP3 and IMAP compatible for desktop software compatibility.
The difference, as I see it, is that one seeks to innundate me with more ADS, and I *hate* ads, and the other is seeking to try to reduce the crapload of spam coming my way. Some people don't care about the Ads. To me, they are more than just annoying. So even if it's free, why would I want to expose myself to even MORE advertisements by giving someone permission to scan my email, even if it is by script, so that they can customise their advertisements? This is my reason for not wanting to try out GMail.
Hope this helps others understand my reluctance. If you choose to use GMail, I wish you the best and I hope it treats you right.

For me, it's just personal preference.