It's great that Seesmic will show when new DMs arrive. For someone who's handling a number of different accounts, though, it would be helpful to see WHICH of these accounts listed in the left-hand menu pane has those messages (DMs).

Also, the same would be nice for @ mentions/replies. When an account has a new @ in it, a notification bubble could pop up next to the account name. The bubbles could be colour-coded to differentiate between @ and DMs (and also state @ xx or DM xx as well).