It is true that the level of water in Iguazu Falls is lower than normal but it worths a visit now, the problem took place during the period from May to August. In the attachement below you will find the latest pics I received from my representative in Iguazu (September 2006). If you want to compare the level now with the level in July, check out this link
http://www.flickr.com/photos/lagneaux/231386538/. Hope this helps...