Mine will be here today. TigerDirect has them in stock and apparently at least the business side of TigerDirect is shipping them. I didn't get my SP3 any earlier though. From the picture at WinSuperSite, the missing driver he installs appears to be for Ethernet. I'll let you know what I come up with this afternoon. I have 2 U2414's daisychained together right now running from the minidispaly port on the SP3
I was under the impression that the dock merely had a "mechanical pass through" for the mini Display Port connector. Meaning, just a male connector on the "inside" of the dock to mate with the SP3, and then just wires connecting to a female connector on the outside of the dock... no electronics involved, just wires.
Edit: Oops, I was wrong... the docking station actually leaves the mini Display Port exposed!
I presume you've tried to connect your monitor directly, without using the dock to verify that it works?