I use iKlear on my ACD (matte) screens, their casings, my keyboards, and MP tower from time to time. I also used it on my PowerBook, Macbook Pro and MacBook Air.
It is a product sold by Apple as well, it is safe if used as per the directions.
forget iklear, or any cleaner branded for electronics
go to a optomistrit and buy an eyeglass cleaner. if it works on deleicate glasses, why not the macbook. been using that **** for 4 years on my devices and macbook, works like a charm!
I really don't think it matters. I've used both iKlear and some off-brand screen cleaner and got the same results. I think any screen cleaner will work.
FYI, I have a 17" MBP w/ Glossy Screen. I now have a Anti-Glare SP on it. But, I did use the off-brand screen cleaner before and after with no problems.