My fault, I should have been clearer.
I was just stating my concerns about a site that would put up a network hash rate that cannot be accurate.
Just to take caution with the rest of their numbers...

Anyway, I am basically going to get around the POS/POW problem by setting up an extra database that will contain the POW difficulty for every block since its implementation. The explorers on CCE update every block when the daemon trips the blocknotify script. I will add the process of getting the POW difficulty for the block currently being mined, along with a couple of other bits of information. This should allow for an accurate hash rate calculation.
The extra information is to allow the users of the getnetworkhash API to use time or blocks when defining how they want the network hash calculated.As of now the API only allows for blocks.