Another problem for TCM HD is that most movies prior to the late 50's were shot in an aspect ratio closer to 16:9, so it would probably not be worth it to transfer them.
This statement is incorrect in several ways, and even if it were correct, it makes no sense.
First of all, if "most" films were shot in an aspect ratio close to 16:9, it would make it MORE worth it to transfer to HD, which is natively 16:9
Second, while it's true that it was more common to shoot in 1.33:1 (basically, the same as 4:3 SD TV) in the early days of film, there are widescreen formats that date back to the late 1800s. And by the "late 50's", super widescreen formats such as Cinemascope were already the norm.
Third, anybody who watches TCM regularly could tell you that the vast majority of their programming is letterboxed. For that matter, the vast majority of the films are from the 50s-70s.
Finally, it really doesn't matter what the aspect ratio is, film is film and it's all suited to HD.
TCM is a natural choice for an HD version, but I think they are just trying to take their time to do it right. I'm sure money is an issue.
Oh, and to mntwister who said the library available to them would be small because the studios haven't made many transfers...Turner essentially IS the studio in this case. They own most of the movies they show. It is up to them to do the transfers.