It depends for me. If the rain is light I just put on the rain top and walk. I never the whole sky fall down on me while I've been out yet but I think I might have to find a bit of cover at that point. If it is morning I might delay packing up camp just to see if it'll subside but not too terribly long.

There are some places where you just have to deal with it though otherwise you'll never get anywhere. I remember last September here in Alaska, I went out into Denali NP for four days and it rained off and on as the clouds moved through the entire time. It would rain for 4 minutes or something like that and then be done for an hour or more and then do it again.

I hate hiking though wearing run gear. Doesn't matter how breathable it is it always makes me warmer and sweaty.