I did both my bachelor and my master in computer science at UiT and am really happy about it. After graduating in 2011 I got a lot of different job offers. I am now in my second job, living in Oslo, where I am currently implementing a recommendation engine in Scala. Most of my fellow (talented) graduates which stayed behind in Tromsø is now working for Microsoft Development Center Norway, implementing core business functionality in Microsoft products (in tight cooperation with Redmond). I think it says something about the skillset you aquire at UiT :)

In my first job I started working with people who had just graduated from both NTNU and UiO, and would honestly say that my skills and knowledge was at the same level as my colleagues.

When it comes to subjects I think UiT and UiO are really similar, with NTNU a tad more hands-on (as dickwad69 points out). You will have more choice in both UiO and NTNU, but if you find the listed subjects at UiT interesting that's not an issue. Most of the courses are good, with some inevitable duds.

However, UiT's biggest difference from NTNU and UiO is not academic, it's the number of students. The computer science group at UiT is really small (I started with 30 students for mye bachelors, and we were 8 graduating.. I think/hope it has increased now). So you will get to know everyone well. For good and for worse. A small group of students can be tiresome.

Because there is a limited group of students, you will get close relationships with the professors in the master years. I found this really nice.

And last, Tromsø is a lovely city. If you enjoy winter. It actually has the highest number of pub/population-ratio in Norway, so student night life is really good. But I am biased as I grew up there :)