Slightly off topic and apologies for it, but I've been using Twitter for some time now and I normally use TweetDeck rather than the standard interface (although on the iPhone I use Tweetie).
As follower numbers have increased, I'm finding one minute updates a distraction so I've dropped my refresh rate to something more manageable.
General updates are now 15 minutes, 5 mins for replies and 10 for DMs. This has made things more easy to cope with but I may drop to lower when getting "real" work done!
I had 624 tweets this morning to go through. I can't imagine how people like Stephen Fry cope!