There's so much camera in the new K20D, to me the higher megapixel will yield a larger print for me. There seems to be no much of improvement over my K10D at first glance (on specs), but actually the improvements are major. The Pentax lens system has always offer great value for money. Other than a DA16-45 zoom lens, I have switched most of my other lenses to the DA pancake primes, and a couple of Voigtlander lenses, namely the 58/1.4 SLII and 125/2.5 APO Lanthar.
I will love to have the new DA*200/2.8 and the yet to be launched DA*60-250/4.
With the new K20D, I am looking forward to higher image quality for my portrait work.