TmoNews grabs the low-down: the T-Mobile Shadow II (which we've been seeing crop up quite a bit of late) should be available on October 15th for $149.99 after rebate. It'll be a solid update to the original Shadow but nothing earth-shattering: Windows Mobile 6.1 will be there, but as of right now it doesn't look like it will support T-Mobile's still-young 3G network.
On the bright side, the included WiFi will support T-Mobile's @home capabilities, meaning you'll finally be able to get carrier-sanctioned VOIP calls on a Windows Mobile device.
Also, new to us for some reason, the HTC codename for the Shadow II is “Cleopatra.” We probably should have been able to tell you that sooner.
The only real question now is whether we're going to get 6.1's sliding panels or if we'll get an update to the original Shadow's “Neo” interface. We know that Sliding Panels can support for MyFaves, so we could see this one going either way. Or both.