Nice piece on the Chao Phraya river in The New York Times:
But after World War II, the focus of Bangkok moved north and east. The river districts fell into decay, their waters polluted. Travelers mostly stayed away and visited the waterfront as part of a day trip to the famous wats. It is only over the last two or three years that the river has been rediscovered by bohemian Thais and intrepid expats, creating a mix of decay and contemporary chic that evokes an Eastern New Orleans.
The river has long been my favourite way of getting around Bangkok too, and it seems I'm in good company. When I first travelled to Bangkok in 2006 I opted for a hotel on the river (the Royal Orchid Sheraton, just up the road from the more famous Oriental Hotel), and quickly discovered that I could completely avoid the hellish traffic by commuting on the cheap and wonderful riverboat taxis (where buddhist monks ride for free). Every time I've been back I've done the same.