Ordered MBA 13 on 16th Aug.. Received on 28th August. Promised DT was 18-22 Aug.

No. I didn't. Apple shipped it out on time but it was stuck at Malaysian customs for more than a week. Since the MBA was shipped in a bulk shipment with other things like ipods, my guess is that this created some problems with customs. So there are three possible reasons for delay at Malaysian Customs

a) Slow civil service at Malaysian customs
b) Clearing agent from apple didn't put it enough effort to clear the goods
c) Apple wasn't quick enough to pay taxes or provide the documentation to clear the goods.

I had a deadline to receive the goods and with 3 days off this week, I was lucky to get it on Monday.