The IRS is counting FEH/MMH sales under the same 60,000 limit (not sure if they are throwing in the Mazda Tribute Hybrids but since there were only a few hundred made it's not a real issue). This was the same for Lexus and Toyota brand hybrids.

The IRS has documents regarding the credit and phase out period at their web site. Such as:
http://www.irs.gov/newsroom/article/...107766,00.html

Even if they announced today that Ford reached the 60,000, the full credit would be in effect until September and then 50% until March (roughly). As of August 2007, the count was around 34,000. There should be an updated count/document by now but I can't seem to find it.

Also note that not all FEH/MMHs built are counted in this number (IRS defines what "qualified sales" are). As best I can tell all of those NYC taxis aren't counted.

Don't forget to check and see if you state also offers a tax incentive for hybrid purchases. Also, check with your insurance provider to see if they offer lower rates for hybrid owners.