I just got my new retina macbook pro 2 weeks ago, 2.8ghz i5, 8gb RAM, 500gb storage. It has been running smoothly whatsoever, but now i am noticing a slight lag when i move the trackpad. It only occurs, sometimes, if i let go of the trackpad for approx. 5 seconds or more, and i have to say that it is a very brief (<0.5 seconds) lag, but very annoying over time when you start noticing it. The lag only occurs during "the first touch" so to speak, the only real way for me to describe it is, as if the trackpad has to wake up when it hasn't been used for a few seconds. The lags also occur when scrolling after not having used the trackpad for a few seconds. I noticed that the keyboard also has a slight input lag if i let it sit idle in a text document (for a few seconds) and then start typing - there will be a slight delay until the first letters turn up on the screen. The lags are very tiny, but i don't notice them on my sisters older non retina 13" MBP. I have already tried to reset PRAM and SMC - and no background processes seem to be eating up CPU..... I have additionally tried booting in safe mode and also done a complete format and reinstall of mavericks without any improvements. It is also worth mentioning that when i plug in an external mouse, i see no lags. Any thoughts on this? Is this common behavior or? Thanks in advance!