I found a minor bug:
I can't get the list of tasks from a smart list with a space in it. For example, I have a smart list titled "Due Today". When I type "rtm lists", it sees the smart list, but when I click on it, it shows 0 tasks.
There is, obviously, a very easy workaround. I renamed my smart list to "DueToday", and it works perfectly. So, not a big deal, but I thought I'd report it.