You're probably right in that the HVR is more a pro-videographers camera, while the NEX argualbly has more photographic origins. For example you get more optical choices with the NEX, but while you can use an external mic via mini jack, you can't attach pro-level XLR stuff. If you don't already use XLR mics it might be less of a big deal. Certainly people seem more than happy with NEX audio capture in general; it depends what level you want to take it to or currently need to work at.
I'd say the best thing would be go and get some hands-on time with both, see how they feel. They're quite different to use and that experience is definitely the best way to inform your decision.
If you're still not sure, you might want to have a browse of Sony’s Videographer forums over at http://www.sony.co.uk/discussions/community/en/pse - you'll get more finely-tuned advice there than you will here on the photography forums.
The main Videographer’s hub is at http://www.sony.co.uk/biz/b2b/business/product/videography? well worth bookmarking for future reference.
Whatever you decide, be sure & let us know how you get on!
Cheers
Mick
