Yes, there will be such a car. The 2009-2013 MTA Capital Plan has this info:
The purchase of 590 railcars described above will be executed under two separate contracts. 382 railcars will be bought under an option of the existing R160 contract, bringing the total number of R160 cars in the fleet to 1,662. The remaining 208 cars will be the first of the R179 series. These longer (75- foot) cars will replace the R44 fleet, which was purchased in the early 1970s.I wasn't sure there would ever be more 75-footers.