Hi there, something I have read about MacBooks but do not know if it applies to the Air, does this happen more when the laptop is plugged in or unplugged? I use my macbook with the plug straight into the adaptor, but it comes with another cable which has a proper earth.
Do a test and see if this happens when you 'ground' your hand on the body of the laptop at the same time.
If it makes a difference, use the extension lead, as you may have a bad earth.
I too have the new MacBook Air 13" i5 with Lion and have this same basic problem (haven't noticed the cursor lag but I will look for it). It goes from doing all sorts of unintended clicks to completely unresponsive. This trackpad was supposed to be an upgrade but I am now missing my old white MacBook.
Luckily, I have not experienced the kernal panics but have had ocassional weirdness with Safari in full screen mode.
Same problem on a brand new 13" Macbook Air (i7, 256GB). I'm used to the buttery-smooth trackpad performance on a standalone bluetooth trackpad on Snow Leopard. On the Lion, sometimes tap-to-click does nothing for many, many clicks. Then it suddenly responds. Frustrating.
Will have to return my purchase within the 14-day return period if no fix is forthcoming.
EDIT: Lion has also completely frozen the system once. Unstable.
Screencasts to demonstrate the problem:
Slow movements version: http://www.youtube.com/watch?v=FM71ra7avlY
Fast movements: http://www.youtube.com/watch?v=GLkmqqQpGjw
In the videos I move the cursor, then tap -- all the time repeating this pattern. If the cursor is still, I'm just tapping, waiting for a response, then moving on.
An update for all on my situation, I took my Air back to the Apple store. The genius tried to run a couple of low level diagnostics, all of which froze up before they even got started.
He scratched his head and then swapped it for a new one.
Since getting my new one, the track pad has been fantastic, smooth and responsive.
If you guys are still having isues, I'd really think about taking it back.
Esperiencing the same problem on a macbook pro about three years old, just upgraded from snow to lion. Major pain. I tried fiddling with all the trackpad settings, to no avail. Very inconsistent problem, comes and goes, sometimes a restart will help. When the problem is present the trackpad is jittery, with frequent unintended clicks causing various unwanted windows to open and close, text to be highlighted when I dont want it to be. Can't return it like Mitchy did..pain.