does anyone know if the cobalt will have a limited slip front end like the 03 (i think) and up srt4

yes, in the performance package. SRT-4 didnt get one til 04.

Like said above the SRT had the equal lenght half shafts in 03 and the Quaife LSD in 04+, The cobalt will have an LSD as an option. It really makes no difference in a straight line.

Well the problem is that the LSD option is not out yet but no one knows when though.