I come at the Poulsbo problem from, pretty much, a plain old 'frustrated user with the time to try and build random things' perspective. The redoubtable Matthew Garrett comes at it from the 'equally frustrated, very smart kernel developer' perspective. His post on the mess is well worth reading for a different angle on the whole deal.
An update on the situation, BTW: I haven't worked on cleaning up the packages for the driver for F11, as I said I would, because of some later experience with it. For both me and a couple of others who've successfully built and got it working, it causes the system to hang solid, quite reliably, about half an hour after you turn it on. Which is a bit of a big problem. With benchmarking, it also seems to be slow even for basic 2D operations, almost as slow as the vesa driver; so it's not providing much of a benefit besides the RandR 1.2 support for external monitors.
An email I got from within Intel hints that some of the proprietary special sauce is required even for basic 2D acceleration to work right. I can't find any indication of this in the logs, but it may be that - even though I sucked as much of the proprietary stuff as I could into the packages - I missed some, or it somehow doesn't quite play right, and hence the 2D acceleration isn't working. I'm not sure.
So for now I'm just using the vesa driver and sucking it up. Sigh. BTW, through this whole three week UK trip I'll be doing all my work from the P. So far this is going pretty well, despite the slow graphics!