I’m a fan of the new VS 2010 Web.config transformations. I use this feature for deployment purposes and wondered if it is possible to use them for debugging too.
I think of using them in the IDE: I want to create different built configuration (with linked transformation configurations); choose one of them; start the web site in the IDE and debug the different configurations this way.
Update
Thanks to a 3rd party plugin, SlowCheetah, this is now possible. Scot Hanselman has a blog post about it.
Original response:
Unfortunately, the web.config transformations appear to effect only publishing sites and building deployment packages.
In our scenario we have two development groups, one with access to multiple environments (in-house) and the other with access to a single environment (offshore). We have periods where the in-house group needs to debug directly against QA, while offshore remains locked-out (so their web.config's must point to the dev environment).
We were hoping to have 1x build-configuration per-environment, and be able to choose the build-configuration which matched the environment to debug against--which, as I understand it is your question.