My latest article is out in the latest issue of the Adobe Edge. It gives a basic overview of using Flex and Ajax and tries to take an objective look at the comparative benefits and difficulties of each (which can be a controversial topic since some people seem to take it as a matter of religion). Of course, I think it is always better to have more tools in your arsenal, and I am a fan of using both Flex and Ajax. Nonetheless, I do want to commend Adobe in letting me take an honest look at the comparison.
The article gives some basic examples of using Ajax and Flex with a ColdFusion back-end. It also gives a brief overview of related technologies and frameworks surrounding both technologies including AIR and the recently announced BlazeDS.
I would love feedback from anyone who reads it, so, please, feel free to comment on my blog.