I agree that it is phrased in a bad way and causing confusion. But I'm positive you'd have no problems at all when you come to Turkey with your personal laptop/PDA regardless of its memory. It should be regarded as "personal effects of the tourist" as it is not something you purchased on duty free shops. I believe the items listed below it just include the merchandise you purchased recently as duty free items, not your personal belongings.

As a matter of fact, in 99,99% of cases nobody will even check (or care) your belongings in the custom so this should never be a problem, but if you want to make sure 100%, maybe you can email Turkish Tourism Ministry or contact Turkish Embassy in your country.

But frankly speaking, I'd never worry about it if I were you.