I am curious if anyone else has noticed this? I am using a 13" mid-2009 Macbook Pro 2.26Ghz CPU with 8GB ram. On Lion and Mountain Lion, a 25 minute episode would take about 12-13 minutes to encode to h.264 mp4 with Handbrake. On Mavericks, it is only taking about 7.5 to 8 minutes for the same files. I have tested the encoded file to make sure they are encoding correctly and they are perfect. On that note I guess it's obvious that I am pretty happy with the new OS so far.