The T43 may be one of the last real Thinkpads.
Since Dell is so in bed with Intel, it would seem odd not to see the i9300 released soon. I don't think sonoma supports AGP or DDR, so if the i9200 is changed to include PCI-e and DDR2 it's still the same as the anticipated i9300 (assuming the Gforce 6800 go is an option). Even in the Swedish data sheet, there wasn't a mention of ExpressCard or improved audio. Sata support is also in question.
I remember at a CES asking when the i8600 would be available with ATI cards (they only had NVidia at the time) They said there were no immediate plans to do so. Dell offered them very shortly after that.
The waiting is the hardest part.