I am using the Cingular with a 7290 (Temporarily running Rogers 4.x software until the Cingular release).
The only choice that I have under Options/Browser/Default.... is "Cingular Browser." - I assume that this is where I would make the browser selection.
I cannot access anything inside my organization firewall.
Sooooo... As far as webview goes, It looks like I am in the outside world using Cingular as the ISP.