there's never been anything to suggest that they've fallen out or stopped working together.
ROTT was the first tour that Alain missed (in its entirety) and a lot of us thought that was the end of their partnership but Alain went away and wrote some cracking bits of music for the 2009 stuff (Shame, Birthday, Carol, Skull etc). let's hope the same thing happens for the next album. if anything, Alain's songwriting skills seem to have been improving (altho he had a few dodgy co-writes on ROTT!).