I've been noticing quite a lag when typing comments in posts online... I'll type a few words and nothing shows up on the screen until I stop typing. Then the rest of the words fill in. This happens in Safari, Chrome, Firefox, etc. But when I type in Mail, TextEdit, etc., as I type the letters show up as fast as I can type. I've got 8GB of RAM, 4GB of free RAM, a MacBook Pro15" i7, 500GB 7200 RPM HDD with plenty of space on it, recently fixed permissions, checked disk with Disk Utility AND DiskWarrior, re-booted, cleared caches, checked for current firmware... what now? This doesn't happen on my other Macs, so I know something is up with this machine. (I typed that entire last sentence in before anything showed up on the screen - then when I stopped, after a few seconds, the words filled in.) Driving me bonkers! Can anyone offer a solution?