It’s been a long time since I have traveled to Bangkok. We had a great time roaming the shopping centers and taking time to talk and drink coffee. There were two new malls. Siam Paragon, next to Siam Center and connected through a walkway with water plays and Palm trees. Very nice. Siam Paragon is for the upper class shopper. To posh for my taste. But on the ground floor there are a lot of food outlets, very nice. Siam Ocean World is also on the ground floor. A place we will take our kids next time. There is also an IMAX cinema. Something I would recommend to do in the evening.
I went to Pantip plaza (the computer/software/DVD Mecca) Hasn’t changed a bit. Still crazy and noisy. Next to Pantip is the (new?) Platinum Fashion Mall. I didn’t go in there. We also were in Siam  tower, Siam Discovery Center and MBK. They are all close together with MBK the best for cheap cloths. After two to three days in Bangkok is enough for me to be overwhelmed and go back to Chiang Mai, where the cows still roam the streets (it is very provincial here compared with Bangkok). Here a list of shopping centers from a link I found.
By the way. Did you know that Spiderman resides now in Bangkok. Or perhaps he is only on a holiday. I could swing from building to building in Spiderman style it would surely be easier to get around in Bangkok (with exception of the power cables that dangle over the streets everywhere)
Spiderman