Well, I've finally done it: I cancelled my Yahoo! Premium email and personalized email address (domain name). I'd actually transferred the domain name to a different service some time ago. I believe Yahoo was still charing $35 a year for the DNS name when most services charge between $5 and $10 (sometimes free). Gmail has far surpassed my premium email account, which also had an annual fee.
I deleted all of my folders, filters, and such and popped down all the email I wanted to keep. Now the account is a plain old Yahoo mail account with ads.
In the mean time, Google just keeps adding services to Gmail. The latest is 20-MB attachments.
Yahoo! certainly set the pace for a while, with the best web-based email service around. There are a lot of people that still prefer it and I'm not planning to cancel the free acount. Their services are more impressive now and the new, fancy email interface is impressive in some ways. However, I simply prefer the Gmail interface. It's incredibly powerful but simple to use.
Gmail is truly a new way of doing mail whereas Yahoo has basically copied Outlook Express, et al.