For all of those people trying to figure out where they are going to live in PDX next year, I thought I might offer some advice. I moved here from Los Angeles 4.5 years ago, and I was in your exact situation my fiancee' at the time (then wife, now ex... not really interesting) was enamored with the quiet serenity of SW Portland and Beaverton. She even managed to find an apartment complex replete with a babbling brook and ducks! Needless to say, that was not going to fly with me, and for good reasons: when moving to a new city, I believe it is imperative that one live as close to the city center as possible (unless it is a desolate wasteland... sorry L.A.) in order to survey out the surrounding areas and best formulate an opinion. Now this does not mean that you should rent a room in a hotel room with daily rates and soak up Portland life like Bukowski, but the closer you can get to downtown (hence the real estate term "close-in PDX... very important, not to be confused with Gresham), the greater access you will have to all the city has to offer.
The public transit system, as mentioned before, is quite excellent in Portland, so much so that you aren't required to live off the 8 line to get up the hill to OHSU. With the exception of suburban SW (don't know it very well, and the following advice makes no sense logistically for that area), you can find and easy connection to the 8 line from the downtown transit center. While in "Fare-less Square" (thing bus-line hub), you can easily get off your bus-line and find a connecting 8... no really, it is quite easy, un-supervised grammar school students do it all the time.
Here is why I've been suggesting the afforementioned approach to P-town living. Portland is a city of unique, interesting, and varied neighborhoods, all of which should be entertained thoroughly before settling down with one. Now I know what you are thinking, we are going to be medical students next year, with very little time to do anything other than study, so why do I have to live anywhere but up on Marquam Hill? If that is your take on your first year in Portland, then please introduce yourself to me at orientation (I'll be the relatively old guy, big smile, bigger head, fond of hyperbole), because I'm really going to want to share notes with you. If however, you are currently entertaining any thoughts on venturing outside on say a friday night or a sunday morning, then you might want to take heed of my advice. Hawthorne (boutiques, hacky-sac, the Bagdhad Theater, and good food), Belmont (veggie restaraunts, Movie Madness, good Theaters (plays), better coffee), Division (up-and coming dining establishments), Mt. Tabor (only volcano within city limits in the continental US, hiking, go-cart races), Sellwood (old Portland, food, antiques, waterfront trails, amusement park), Brooklyn (families, close to the ( line into downtown, city views, concert venues), South Waterfront/Macadam(the soon-to-be tram, waterfront activites, small town feel), Multnomah Village ( even smaller town feel, close to OHSU, brew Pubs, convenient access to sundrie goods), Downtown (food, nightlife, pan-handling, live music, pioneer square at twilight, Park Blocks), NW 23/Alphabet Blocks/Snob Hill (shopping, hiking/adventure at forest park, close to zoo, IMO best restaraunts in town) The Pearl (yuppie-lofts, East-Village vibe, Powells Books, great food, First Thursdays, More Brew-Pubs), ... etc. This list merely scraped the surface regarding the superlatives used to describe but a fraction of Portlands neighborhoods. I've learned about them by getting in a car, driving to a new area, and getting lost on a Sunday afternoon. If I liked its vibe, I made sure to come back with my dog... I'd invite you to do the same (not with my dog though). So there are my 2 cents, and I can't wait to meet all of you when you get to Portland, whatever neighborhood you decide to settle down in.