I think it depends on the make-up of the clothing, and how important it is that they "look nice". It's never been a concern of mine, so my basic rule is the same as opinestle's. Most of my clothes are VERY casual, T-shirts, jeans, etc., so I don't care if the black clothes look dark black for a long time or not. If I had nicer clothes, I'd pay more attention to temps, etc. (which is one of the reasons I *don't* have nicer clothes!

) I've been hanging my clothes out on a line again for a while (after doing it my entire childhood), and I LOVE doing that. There's a little exercise, the clothes smell fresh (even tho I'm in a large city), I'm saving lots on the power bill, the whites are whiter.
The FlyLady has collected laundry tips from her readers, you can read
Part 1 and
Part 2 online.