No more E46 Sedan/Wagon from this summer, so they will use those lines for the new E90 3-er.
But yes, they are pushing it, 1-series, 3-series, 6-series, and the new M5, plus a face-lifted 7-series. Lots of activity at BMW, hopefully the quality will not drop....
As for the powerplant, a 3.6L V8 is rumored for the 335i some time in the future. At the beginning, I bet they will use current engines, but maybe bumped up to the ZHP output for the 3.0L.
M3/M4 will have retuned current M5's V8. It's lighter than the 3.2L six being all-aluminum.