They have had several issues in their first few experiments with HD, one being that you could hear wrestlers calling out their spots and it is very easy to see when a wrestler misses a move. Several more rounds of testing are yet to come.
Another issue that arises with HD is how the Divas will come off on TV. According to several people, HD is very unforgiving when it comes to make-up and less than perfect bodies. There is also a concern that the older wrestlers, like Michaels, will show their actual age in HD.
CW said they are ready to go HD for SmackDown tomorrow, if needed. USA, however, is not ready at this time but will be within the year. So we will have more on this in the coming months.