In reply to antwan:
I am loving my OU Maths degree, the quality of the course material has been excellent and tutor support is generally good.
The Student Home website is also very good, with tutor-moderated forums to ask questions and discuss the material, online tutorials by tutors, etc.
The tutorials have varied from course to course, on my current level 3 course I get 4 6-hour day-schools, which is pretty good.
The summer school I went on was an absolute blast, but I think the OU are phasing them out.
Cost has been manageable (I am in a transitional arrangement since I started in 2008), but I don't think I could afford a degree at the current costs.
I'm planning on doing a Master's at Southampton after finishing my degree and chatted to one of the admissions tutors. He reckoned an OU degree was just as good as any other. To get a Distinction (equivalent to 1st class) you need to score above 85% in both your assessed and examinable components. The exams are tough, so it's a challenge.