Headrat - I see that your disk configuration has changed since the begining of this thread. Can you explain how you managed the upgrade?
Yup, just a bit of data shuffling, one of the nice features of WHS is that as long as you have enough space you can just "remove" a disc from the pool.
I bought a couple of 1TB discs, copied some data off of my WHS until I had enough space to "remove" the other discs from the pool, I then pulled the smaller discs and replaced it with the larger 1 TB devices.