You get Trados 2007 SDK documentation in the installer included, you just need to explicitly select it for installation, it's not installed by default.

If you don't HAVE to, no need to upgrade at all.

It's worth noting that the SDK documentation is not complete - the "Jobfiles.chm" file, describing structure of the job files used for Analyze, Translate and Cleanup actions is missing.
You can get this file from "Trados 6.5 LSP" package, which is also downloadable from the FTP (it's in the root).

EDIT: Actually, the jobfiles documentation is there, under Programming Guides... but references to the jobfiles from the Programming Reference (e.g. TW4Win.TranslationMemory.AnalyseFiles method) still link to the original external CHM file, i.e. are broken.

As far as I can tell, no special license is necessary to USE the SDK... (at least not with 'higher' licenses than Freelance).
That special developer license was necessary to GET ACCESS to the SDK back in the ancient days when it was not included in the installer.

Unknown said:

Someone at SDL should finally realize that not everybody on this planet is a developer with Visual Studio, but still would like to get some Trados Studio stuff automated.

Might be true, but I'm pretty sure the current situation is more powerful and more widely used already. You can always use Windows Powershell, this is pretty simple for automation.

Paul, the point is that
1) The users I'm talking about do NOT need the power you guys are so excited about... they do NOT want customize/redesign the interface, nor they have ambitions to create plugins, etc... All they want is some EASY(!)-to-create automation of pretranslate, cleanup, etc.
2) The power of the API has NOTHING to do with the way it's accessible (COM/.NET/etc.). Just look at the Microsoft Office - even the latest version can still be automated using simple JScript/VBScript file written in Notepad, using all of the latest features and API enhancements!

Regarding PowerShell - have YOU personally tried to write some simple T2007 automation in VBScript and compare it with TS201x effort needed for the same automation using PowerShell?! I seriously doubt that, it looks rather like you just repeat someone else's (most probably a developer's) words.
Have you tried to get the 'glorious' PowerShell Toolkit and actually _USE_ it with TS2014/2015 installed on Win7 or Win8? It's NOT possible 'out-of-the-box'! One gets some weird god-knows-what-it-means errors (and it's NOT about the paths, of course!) and it simply does not work.
And then what? If you are not developer (and remember, we are talking about NON-developers!), you are screwed.

So I strongly suggest everybody to get realistic and get out of their offices and talk to real common users...