Well, SCVMM 2008 Beta & Hyper-V RC0 had a great time together, however, some of the major interface changes that have gone into Hyper-V RC1 mean that RC1 and SCVMM 2008 Beta are on a bit of a break.

Fear not, as Rakesh details on his blog, the relationship will be back on fairly soon :-)  In the mean time, I'd choose one or the other, and wait until the patch is available.