It is cheaper up north but that is partly due to the salary difference.
To echo comments from other posters : Go if you can secure a job there first.
But it's all about current and potential opportunity. I live near you and know the surrounding areas quite well, but Cambridge suits my line of work. Currently I'm a VMWare Systems Engineer working for a Managed Services Provider, I also work at home 80% of the time.
Being near Cambridge suits me. Cambridge itself is good for tech jobs, there's also a lot of investment in Peterborough - Associated British Foods opened up a new datacenter there, and I was interviewed for a position at that company.
Plus I'm ~6 miles way from a train station with 45min trains into London. The company I currently work for are based in London so I do have to go down there every so often.
Saying that though, a few years ago I wanted to move to York. I just love that place. But one of the issues was jobs - yes there's Leeds next door but I hear the commuting was dire and still couldn't compete with the level of opportunities I have here. With how things are in this country at the moment I've positioned myself in a "safe" zone for jobs that match my skills.