According to The Wrap, it looks like Seth Rogen and Chris Pine are both in the running to star with Reese Witherspoon in This Means War.

In the film, two best friends, inseparable since childhood, who fall in love with the same woman (Witherspoon). The two men's bond disintegrates and their ensuing battle escalates to mammoth proportions, with New York City demolished in their wake.

The Wrap goes on to say that Rogen might take over a role in the film that was originally offered to James Franco.

Aside from these rumblings, there really isn't any solid casting news regarding these roles for this project.