One of the main features of VST instruments is that the audio output of plugins is immediately available within the host sequencer; I wouldn't expect this to be any different for VE, and indeed I'd be disappointed if I had to concoct some ropey lash-up to get audio back to the sequencer for further mangling and wrangling.
Even if VE ran standalone, I would be very surprised if I couldn't route its audio output anywhere I wanted to using ASIO rather than copper, since I can already do this with standalone Kontakt instances routed back into Cubase, for example.
I would expect this to work whether or not the actual instruments were hosted on the same computer as the sequencer, since I see VE as a solution to both the problem of managing many instruments within the host, and the problem of scaling many instruments across the computing resources within kicking distance.
Of course, this could be just blithering optimism on my part, based on my belief that VSL actually employ programmers who know what they're doing.
Breathwise, I batedly await real facts from Herb et al; miserywise, I await being put out.