I mean, that light rail system is just, man. It's no wonder the Twin Cities are (one of) the most bike friendly cities in the country -- if you're not driving somewhere it's the only other way to reliably get where you're going in reasonable time :)
The only way to reap all of the benefits of Minneapolis is to work/live downtown. However, most of the tech jobs are in the burbs so it's a problem! Furthermore, downtown minneapolis is pretty lame. All the cool events/restaurants and bars are not found downtown.
IMO the one thing that saves our mass transit is that busses are allowed to ride on the shoulder bypassing most traffic. I lived in the north burbs and had a job downtown Minneapolis. I could take an express bus from a nice ramp facility to right into downtown with just one extra stop. 20 minute trip vs nearly an hour in a car.
However, forget about using mass transit if you're trying to get anywhere outside of downtown Minneapolis.
Also, the cities are bike friendly but not as friendly as most 'best places to bike' actually say they are. Most articles go by sum of miles of bike lanes, but many bike lanes here are pretty terrible. Not protected, poorly maintained, not plowed or light enforcement for cars badly parked. I'd say Minneapolis is as bike friendly as any other ubran area with a sizable health conscious population.
I have always been really interested, but never found any actual companies and jobs that I felt would represent a good career move.
With that being said, the best way is to pull on a professional network (natch) and the best way to build that network is to attend some of the tech focused meetups in either city. Ruby.mn is pretty popular if you're into Ruby (or just wanting to meet devs in general).
Otherwise the safest route is to join up with one of the large firms and build a network from there to branch out into more smaller gigs if thats your thing.
Fortune 500 aside, there are a lot of smaller startups in the cities. They mostly focus on creating products aimed at the health insurance industry though, which in my experience is fairly dull work.
I'd say availability of tech jobs in the "sort of interesting" category is great in MSP, but the truly amazing jobs are still rare.
There are some downsides of course, the winters of course and there are some racial social issues (not addressing here to avoid derailing thread).
With all that being said I am looking to add some good software devs to my green field project at a very big local player in the medical insurance field.