This is planned. But meanwhile it can be nice to know that there is a very easy workaround.
Most (actually not all) pages adds geocaches to the "current vgps list". So, open VGPS in a new browser tab, switch vgps, close the tab, and start adding the caches. They will then end up in th new one.
I think that it's only livemap that does not add to the current one. But I am not certain, so test it before you add too many.