Ethan Tweedie pointed out another Adaptive Wide Angle Filter tutorial. I posted a tutorial on this same subject by Russell Brown back in June. But Ethan pointed out that this little tutorial is shorter, more concise and focuses more directly how real estate shooters will likely use this fantastic new feature of Photoshop CS6.
My workflow is as follows: on import into Lightroom I have my basic preset that converts to DNG file and applies the lens corrections etc. I then edit in LR4 and CS6. Normally when I am done editing I then use the Transform tool in CS6, but this tool does a great job and is easy!
I have to agree with Ethan, if you have significant straightening to do I like using this adaptive wide angle filter better than LR4 lens correction feature.