I may be overly suspicious, but the way the notice is written leads me to believe there's a lot of spin going on. The changes do appear to benefit users of Yahoo, which is apparently TMO's new service of choice. As others have pointed out, though, there might actually be a net loss of function for those of us using different setups, particularly forwarding to the
account.
I have only one low-traffic ISP account actually integrated with the BWC. The rest of my mail comes through the redirector for corporate mail, through Gmail forwarding, and through an auto-forwarding app that picks up my Hotmail and e-mail from other personal accts. My sent-from and auto-BCC are set to Gmail. After the change, I suppose I'll have to lose my Gmail forwarding and set up POP integration in order to retain my sent mail in that acct (and, unless we retain the ability to set a default "sent from" addr, to avoid having reply recipients learn my blackberry.net addr). I will also have to set up my auto-forwarding app to send my mail to Gmail rather than directly to my blackberry.net addr. So, for all of those accts, it looks like I'll be back on the BIS polling schedule, up to a 15 min wait. It is also worth pointing out that Gmail POP has had a few weird glitches, at least early on.
I suppose I could have Gmail and the auto-forwarding app direct my mail to Yahoo, but then Yahoo would become the repository for my sent mail (no auto bcc option to send it elsewhere) as well as my new "sent from" addr. And if, for some reason, I was using Hotmail to store my auto bcc sent mail, I guess I'd be out of luck, since I don't see any indication that TMO is lifting its restriction on Hotmail integration, which would be the only way to get sent mail there.
Seems like a real coup for Yahoo at the expense of the other major free e-mail providers. I don't yet have a clear picture of how the improvements to standard integration will work, but I'm not sure at this point that they will offset the apparent loss of functionality for those of us forwarding mail to our blackberry.net addrs