I started my own guild awhile back and was 4 boxing shamans in ICC 10 and we got to sindragosa, but around that time I merged with another friends guild so now we had lots of people we were running 3-4 full clear 10man grps a week an ICC 25. So I was just playing my hunter or main shaman in the 10man grps and running 25man 4-5boxing, and it worked out well.

I've been multi-boxing since everquest I don't really see myself completely quitting multi-boxing. I think boxing will still be viable in cata, but it will just be diff. With 10man and 25man raids dropping the same gear that motivates me to stay 4 boxing 10mans, but I haven't seen the fight mechanics yet to know if that's fully possible.

If I do go back to 1 char my toss up is between Lock/Sham/Hunt/Rogue.