Not that they are known for their accuracy, wikipedia claims that TruTV IS in HD.
truTV - Wikipedia, the free encyclopedia
It's not sourced, so take it with a grain of salt.
I like that AVS forum chart I linked above, because it's based on actual reports from viewers. While they list channels in yellow that have been "announced", anything in green has actually been reported as on the air.
It's updated pretty regularly...they've added Logo & BET-J, showing on DISH only. Of course, those channels haven't even really launched yet, but the chart is based on viewer reports. So it won't let us know whether there is really a truTV-HD or TCM-HD, but it will let us know if some cable company CLAIMS to have it.