My connection is fubar at work ... so I can't really look through this thread. That said, I'll take a shot at some of the things I expect to be in here.
1) 40GB HDD - In an of itself, seems unlikely as a major price reduction. Exactly who is making them in quantity at this point? A 40GB HDD is unlikely to save Sony money right now (or at least very little), and will likely cost more than an 80GB very soon.
2) USB - You can't remove them, since they charge the controllers. Beyond that, the cost savings are insignificant.
3) BC - The GS could be removed to save money (and PS1 compatibility would remain). Again, how much does it gain them though? It could be enough to be worth it for an overall price reduction. By itself however, I don't see it being enough to create a viable 2nd SKU that actually is of significant savings.
4) DVD/CD compatibility - While CD could be removed, DVD cannot if Sony wishes to continue advertising PS3 as being BD compatible. DVD support is part of the BD spec, so Sony would have to remove all mention of BD on the SKU ... including listing it as BD compatible.
