If they do get VdV, that gives them three attacking mids with Modric and Kranjcar. Along with Huddlestone, Sandro, and Wilson "I can't pass" Palacios, that's a pretty crowded center midfield.
I think loans can still be made, but they can't be registered once that deadline passes. Would mean they could only go League Cup games until the next window.
Gyan might work well off of Bent because he's fast and somewhat strong, otherwise I don't see it. A striker that can't score isn't going to help too much.
"Just heard from a reliable source that Steve Bruce is to make a late effort to lure Ronaldinho to the Stadium of Light from AC Milan if the signing of Asamoah Gyan falls through, which appears to be likely with agreeing personal terms the problem. Watch this space."
Definitely, there's no use adding a few more very good players to an already filled team. They needed a big time striker and and another top class player or two and it just didn't work out.