Blog-Reference
The conclusion “‘New Keynesian’ models are not too simple. They are just wrong” is beyond a reasonable doubt, but this applies also to ‘Old Keynesian’ models. See Why Post Keynesianism is not yet a science and Mr. Keynes, Prof. Krugman, IS-LM, and the end of economics as we know it.
For the summary on Wren-Lewis' DSGE models see Much change, no progress.