'Aren't they suppose to leave the farm at some point?'

The sooner that happens the better, I'm getting really sick of that farm now.

*spoilers*

It would be awesome for the other members of that gang to find the farm and all the gunfire attracts a horde of walkers, forcing them to leave for good.

I respect your opinion; however, I think Shane is arguably the most pivotal character on the show right now. He's the only person keeping things interesting if there isn't a zombie in the mix, and when you consider his ties to Rick, Lori, the unborn child, Andrea, among others, it's easy to see how the show would fall apart without him at this point. Everyone else on the show has no personality; they're all far too passive. Daryl WAS a good character, but lately it seems as if the writers don't have a clue what to do with him. His silly outbursts as of late don't cut it for me. He's an interesting character and a valuable member to the group, so they need to write him that way.

Anyway with regard to Shane, there aren't many indicators that he's getting any calmer, so while I do think he's going to have to die eventually, now is not the right time to do it. The best time for Shane to kick the bucket IMO is if some of the characters start having attitude changes leading to more conflicts, a new catastrophe occurs, or additional characters are thrown into the mix that aren't as well behaved and mild mannered as everyone else.

MAJOR SPOILERS BELOW

He just signed a deal to be on the new Show LA Noire (no affiliation with the game) as a main character. So rumor has it that sealed his fate. To further the claims advanced information on the show state he goes on a search with rick and doesn't come back.