Cadillac is working on a brand new car that will compete with BMW's very own 3-series. It's going to be built on the new Alpha RWD platform. The same Alpha platform will be the basis for a folding hardtop coupe, or a conventional coupe and convertible.
On the other hand GM put on hold the DT7 project to make this one (the program to combine the STS and DTS models into one, rear-wheel-drive flagship sedan). The DT7 is now set to be revealed in 2012 and not 2011 as previously announced.