New Issue just popped up for me on Wed. the 9th and has persisted.
At first, I thought it was my vid card, but have spoken to others that are having the same issues. After a decent amount of playing (1hr +) my client's frame rate will plummet for 1-2 minutes making the game a slide show and then return to normal for about 10 minutes, then happen again.
This has happened in KSE, the pvp C&H map and once on DS9. I have and NVIDIA 260M with the latest drivers. I updated them on Wed after this issue appeared.
I have tried lowering video settings to rock bottom, disabling combat logs, verifying all files, all the obvious fix attempts. Other games (ME3, TSW etc) work fine. This is the first major video issue I have ever had with STO and I have been playing since Beta.