I can't tell you a lot about Corvallis specifically, but the Pacific Northwest is a fun place to live. The weather is much different from Texas. We do have a lot of rainy days, but we have enough coffee to get us through. Corvallis is about 90 minutes from Portland, where you would spend your third and possibly fourth year of OSU pharmacy school. Portland is a pretty standard city - it kind of reminds me of Austin. There is a lot of the usual stuff to do - concerts, galleries, places to eat, urban hiking. It is a very green city with a huge emphasis on biking and recycling. It is close to skiing at Mt Hood and close to the beach, though the beach is really cold. There are lots of outdoor activities. Oregon is not the most diverse place you'll ever find, but it is filled with young, open-minded people and I am sure the demographics will change over the next few years. As a side note, a 1 bedroom apartment in the Portland suburbs will run you about 500-650 a month. It is common here for people to rent rooms in houses with a lot of other students/friends/young people to keep the costs down (that's what I do).
If you interview in Corvallis you will fly in to Portland and I would recommend you spend a day checking out the city. The third and fourth year OSU pharmacy students meet at OHSU's brand-new fancy facility right on the water. It has a great view, but no parking available for students (there's ok public transportation).
I know this didn't clearly answer your question, but it is really hard to summarize it all in a reply, especially since I am not that familiar with Corvallis. Craigslist is huge in this area so you can visit the activities and general sections to get an idea of things happening in the area.
As far as my personal choice, I applied to OSU for the in state tuition, but I wouldn't mind going somewhere a bit warmer and less dreary (though this area itself is really nice). Good luck and please email me through SDN if you have any specific questions that I can answer.
