I thought I was the only one that witnessed slower screen updates. I don't know if it's the same thing, but for example, holding backspace to delete a few characters seems to lag (on an SSD with 2600k @ 4.5ghz and 8GB DDR3). I know I can just do C-u, but the lag is irritating nonetheless. Not to mention I actually like Terminal.app so I don't have a problem continuing to use it.
The original versions of iTerm gave me this problem, but since it was forked and called iTerm 2 I have never, ever had this problem. Are you using the newest version?
