More recently, I 'upgraded' to a bluetooth keyboard and a 'magic' trackpad or whatever Apple calls it. I like the trackpad's swipe-y gestures, but they both disconnect from the computer at random intervals. Sigh.
Then, within the last month, I caught myself switching back and forth between the trackpad and mouse a lot because they were both "sticking" -- intermittently failing to track my movements.
To get through the workday, and start diagnosing the issue, I got another mouse from our sysadmin. Unfortunately, he only had bluetooth "magic" mice. (If I want to see a magic mouse, I'll go to Disneyland, thank you very much!) When I went to pair this new bluetooth mouse, I accidentally paired a co-worker's mouse instead -- while he was using it! I moved my USB mouse to his machine so he could re-pair the bluetooth mouse with his computer. He quickly diagnosed that my wired mouse had a short, which caused it to usually stop tracking if I moved the mouse straight vertically.
Once we got the bluetooth paired, I started thinking about really solving my mouse issues. I brought a Microsoft wireless USB mouse from home and tried that as well.
1) All mice are flaky sometimes
2) Some (all?) of the wired mouse's flakiness can be explained by the short; holding the wire straight prevents it.
3) Both the bluetooth trackpad and the bluetooth mouse are flaky sometimes. Is it the bluetooth? Is it an OS or computer hardware issue?
4) The wireless USB mouse is a little flaky at work, but not at home.
I think this leads me to blame either my Mac Pro or the desk surface at work. Neither of these have changed conspicuously since before I started noticing these issues.
Upgrading from 10.7.0 to 10.7.2 did seem to temporarily alleviate some flakiness. Maybe it's drivers? Maybe simply a reboot helped?