Who is using the Stellaris CORTEX-M3 and for What Type of Applications?
1) The Luminary/TI CORTEX-M3 Stellaris product line seems most straight forward in terms of tools and documentation. There are many supported development IDE environments. There seems to be a good set of peripherals for most applications that don't require allot of high-end number crunching (e.g. DSP); RAM and FLASH space are acceptable, but there often is never enough of either right?
2) NXP seems to be a more recent entry with a well supported attempt to add parts but seems to be tightly coupled with Embedded Artists and Code-Red Technologies. Not really an issue as both Embedded Artists and Code-Red are very aggressive and produce high-quality tools, but I prefer alternative to evaluate (read: Not free, but lower cost IDE).
3) Atmel seems to be having a harder time catching. I base that on some of the posts I've read on their forms (e.g. posts asking where to find production parts and posts). The Atmel SAM3 seems to be so new to the payers that Ateml doesn't quite seem to have a good variety of IDE support and the documentation is still preliminary.
All three companies offer the Keil/IAR evaluations though graduating to the "production" IDE is out of my price range. I've used CodeSourcery, Rowley, and Code-Red NXP Express in my evaluations. I found Rowley to be straight forward with minimal IDE "features". The Eclipse-based IDE's were more difficult to cope with, but easier as time went on.
So, I rambled a bit here; my purpose was to "ping" the group to see what others think primarily of the Stellaris family to validate or persuade me that I am on track.