This was my first full marathon, and apart from a really bad IT Band blowout halfway through, it's one of my favourite running experiences.
The course itself is standard city marathon fare: running over some famous bridges and past a less-than-famous railyard, and everything in-between. Great community support, too! Almost every aid station had gummy bears, which when combined with careless grabbing and consistent misty rain all day made the road a rainbow-coloured gummy massacre! Amusing in a sugary-macabre sort of way: just like Portland!
And the finish was one of the more epic finish lines I can recall. The atmosphere was electric, felt like the Olympics!

TL,DR: A solid city Marathon which rain and clouds cannot damper.