I think there not worth much for a number of reasons. Firstly they are a mixture of numbers and letters which is always bad. Secondly quad core processors may be the latest now but in time these will be considered obsolete. Thirdly why 2? Quad core processors will have 4 cores right? I think these are worth reg fee - xx at most.
RegFee unless Technology introduces this. And I have a feeling Intel will think of something crazy for their Quad Processor names. Why would they call them core2quad if they are going to be core4?
The reason why Core 2 is in the name is because there isn't really a quad processor in it, rather 2 Core 2's. I thought if a site like Toms Hardware was reporting on this then the names would be at least in some way accurate.
And yeah, like any technology name they'll have a pretty short lifespan. However it seems as though it might take a while for these processors to proliferate their way into the market. I bought a laptop last month from a popular retail chain over here in the UK and it still had the first Intel Core Duo in it. It might take between 6 months and a year for these to become affordable enough to work their way into most home users machines.