please don't flame

But if the new Nehalem mac pros utilize new technology such as DDR3 ram instead of fb-dimms, and the nehalem architecture is fundamentally different from the penryn, will this render the current octocore mac pros obsolete?
I purchased my octo for two main reasons: I needed a machine at the time for work, and with the intention that I would get 5 years of life at least for this machine considering its price.
I know some would suggest upgrading when the nehalem come out, but considering I just purchased it, plus the cost of at least $1,000 to upgrade makes that option unappealing to me.
any thoughts from the more experienced mac gurus here?