Actually, you should be eligible as a business for the "Advanced Lean Burn Technology" credit. See:
Summary of the Credit for Qualified Hybrid Vehicles
Scroll down. Businesses claim the credit on form 3800. I presume this applies for "lean burn" as well as hybrid vehicles.
The TDIs have not yet been added to the IRS website yet, but the thread at VWVortex seems to have an official VW press release here:
VWvortex Forums: Buyers of Volkswagen Jetta TDI vehicles eligible for a $1300 Federal Tax Credit
Won't they commit to MSRP? Delivery is another story. It seems the manual TDIs may be delayed, from what I've gleaned from the rumor mill. Don't ask me for a source, I don't remember where I read it but I seem to remember hearing December?
Since running the numbers I'm still on the fence, but I think a SportWagen TDI is in my future as long as my local dealer doesn't tack on $ in addition to MSRP. Some dealers around the country are already marking them up by $2k or so, apparently.
CDH.