I would probably just use water and a microfiber towel. Using iKlear solution on the MBA gives it nasty smears -- similar to having a fingerprint smudge smear.
Water gets the job done quite well, however.
I used an iKlear travel single on a small area of my new iMac last weekend, and I can't get the smeary gray smudgy look off of that area. I've used several clean microfiber cloths with a lot of effort to no avail. I'm going to try water.
Was your iMac hot at the time? I've only ever seen that happen when it was hot.