Yesterday I was playing and another player (Awsm) kept switching from his team to ours and tearing down everything we built. Are there any thoughts on how griefing like this could be stopped? Like no switching teams unless they are unbalanced?

Gameplay balance is tricky because changes made in order to address one problem often creates new problems.

And griefing occurs regularly by players within the same team as well, without switching back and forth. I have to admit it's pretty satisfying to tear down something someone spent hours building in 5 minutes, even though it's pretty lame ;)

I think a more general solution to griefing is needed, but it's tricky.

One possibility would be to only let whoever placed a block take it down, but that would lead to people fencing each other in etc... I dunno...

I guess you didn't know that you can votekick then.

From what I gather you type "/votekick ##" where ## is the number behind the offending player when you press and hold the tab key.

I did try to vote kick him. I announced to both teams what he was doing. He then said that the person who was running the server was his friend. Then I was kicked.

Don't join awful servers then.

Durrr good solution.

Then all you can really do in that situation is to either put up with it or find another server :[

EDIT: Oh yeah I don't remember where I read it but I think someone said something about how players who switch teams should be punished with a 20 second respawn time or something like that.

Yes, it is a good solution, obviously. Seeing as if you're getting kicked for wanting to kick griefers themselves, the server is obviously not worth your time.