I was gonna start a new thread on this but...
Anyone notice that Cingular calls their Web Client "BlackBerry Internet Service (BIS)"?
Go to this page:
http://www.cingular.com/midtolarge/blackberry
On the right side, their is a link for the "BIS E-mail Login" but that's a link to the web client. I really hope this is just them preparing for a Cingular BIS and it just links to the web client until it's ready...