Happened to buy from All IT Ikano & Digital Mall last week:

Bought portable DVD writer in Ikano - swipe with MBB2Amex, no charge.

Bought LCD monitor in Digital Mall - card got charge, so paid by cash.

For Amex RM3 million cash back promotion, with additional cash back credited yesterday without any complain, my total cash back is accurate up to my spending on 28 Jan 2013, with the exception of Pizza Hut 1-Utama which was not given.

Eligible amount spent: RM1,613.40 (including RM61.35 at PH)
Total cash back received: RM232.80

I guess the amount of RM3 million is just a promotional value, Maybank would have given more than RM3 million cash back for the 2-month promotion.

Just noted that I was credited with another RM9.20 for "RM3 Million Cash Back" on 3 May 2013. Thus I got the full RM242 cash back for total eligible spending of RM1613.40, the last transaction at Parkson on 28 Jan 2013.