Keyboard lag and other keyboard issues

Hello everybody! I've upgraded to Lion and am mostly enjoying the new OS. However, a problem that I've found quite prevalent has been input lag. It's not happening as I type this, but sometimes when I type something it'll take several seconds for it to come up, with the computer slowly bringing up each letter. It's never done this before, and processor usage doesn't go up when it happens. I also had a problem not too long ago where the keyboard stopped inputting text. I could still use it to switch Spaces and show desktop and such, but it couldn't be used to type into any app. Unplugging and replugging didn't fix, and I ended up having to restart. Is anybody else having these issues? And if so, has anyone found a fix?