If only it were not for the weather....
I should also note that this summer has been absolutely magisterial.
For those who suffer from S.A.D. (as I do), there are options: get a UV lamp. I also recommend acupuncture (how very PDX of me).
As for Portland itself, a friend told me to watch the show Portlandia before I went. At first, I thought the show was way too over the top to be funny. After actually spending some time there, it became apparent that if it was any less over the top, it would be a documentary.
On the plus side, Oregon is very nice. Crater Lake is spectacular in the winter, and perhaps the most beautiful area in the US. There are also many awesome Art Deco bridges along the coast.