I'm so exicted for when Merle meets up with his original group again. I'm assuming that he'll meet Andrea first seeing she will reach Woodbury first then he'll run into the rest.
I think that himself and Daryl will be happy to see eachother but not for long as i think Merle will won't Daryl to join Woodbury but to Daryl's disprovall which will cause a rift. I also think he has some unfinished business with T-Dog and Rick, i wonder what he will do once he finds out that Lori and Carl are his wife and son OMG i can't wait XD
and i've also re-watch the season 3 trailer hundreds of times and i'm 99.9% sure T-Dog and Merle are fighting eachother.