I am not a Lawyer and this does not constitute legal advice.
In the past Adobe employees have said something like "We are not allowed to give legal advice. It is up to you to discuss the Adobe licensing with your own lawyers in respects to your own business goals and plans and decide whether or not your plans are allowed."
To put it differently, "We can't tell you what you can do, but we'll sue you if we think you got it wrong." It is a sad commentary on nature business of business today.
My own interpertation is that creating something using Flex Builder 3 as a tool that enables you to develop quicker should be perfectly okay. I know hundreds of people doing similar things.
If you are worried about Flex Framework / SDK licensing, I also believe that you should be okay to create applications and sell them as you see fit w/o legal impliciations.
If you mean that you are using Flex Builder 3 as a starting point for your own application and want to release an IDE or some similar tool that integrates with Flex Builder, or uses so much of the Flex Builder core that there is no longer a way to distribute your product without also distributing Flex Builder, you are into a grey area here and will probably need to have a long hard talk with your lawyer, and possibly get some form of redistribution agreement from Adobe..
Did I mention that I am not a Lawyer and this does not constitute legal advice? It's an important point.
Thank you for that insight, it actually jives with what I've been assuming, which is to say I wouldn't expect it to be any different than creating an application using a licensed copy of Microsoft Visual Studio or building dog houses with tools I bought from Home Depot. I do understand though that any actions we take will be our own responsibility and I promise that we'll never say "but Jeffry Houser said it was ok!".
It's also worth saying that we're not done "making sure", either, I just needed to see if there was anything obvious we might be overlooking as we get started.
With Flextras ( http://www.flextras.com ) it could easily be said that we are creating derivative works on the Flex Framework for commercial purposes, reusing a lot of the Flex Framework code and tying into the component LifeCycle.
But, based on the way we understand the licensing terms, we are not in violation of the license, so it's all good.
I expect most finished applications written using the Flex Framework would fall under the same category and be perfectly legit.