How does what you posted prove that GM45 is lacking high definition content playback capability? How does that prove X4500HD is lacking in performance?
I posted earlier, with real benchmarks, from notebookcheck:
http://www.notebookcheck.net/Intel-Graphics-Media-Accelerator-4500MHD-GMA-X4500MHD.9883.0.html
Not only X4500HD outperformed the entry level discrete graphic cards from last year, its almost on par with Nvidia's last generation mid-level discrete graphic card (GeForce Go 7400).
Is it strong by any means? Absolutely not. Is it competitive against AMD's 780G? Not at all. What X4500HD signify, however, is that Intel is already making significant improvement on its IGP technology.
On the other hand, ATi's IGP doesn't seem to improve that much at all, if 3DMark06 is of any indication. The difference between 690G (HD2400 core) and 780G (HD3200) is a measly 300 points.