i have seen several threads about this, and my advise is that it is always best NOT to use a beta as your main op sys. there are too many kinks to work out, and you could lose everything. also, ms has an automatic uploader built into the beta, so you are continually sending information back to ms.
the best thing to do is to partition your hard drives, and put the win 7 rc on the other partition. if you have two drives in your computer, then it is better to have them on different drives. then you can boot into win 7 and use it as much as you like. but WHEN you run into problems, you can easily boot into your old op sys to do whatever you need to do. this has worked beautifully for me. and i will continue in this manner until the official release of win 7. just my two cents worth...
the best thing to do is to partition your hard drives, and put the win 7 rc on the other partition. if you have two drives in your computer, then it is better to have them on different drives. then you can boot into win 7 and use it as much as you like. but WHEN you run into problems, you can easily boot into your old op sys to do whatever you need to do. this has worked beautifully for me. and i will continue in this manner until the official release of win 7. just my two cents worth...