this is an extremely late reply, but here goes:
I think the linktheater is a networked media tank, though it does not have wireless support (not even through a USB dongle), or the ability to plug a SATA Hard drive to it. The menu is a bit slow and looks outdated.
(I've read somewhere that there are 2 major types of NMTs in the market, the ones based on Syabas technology, and the Xtreamer which is based on their own developed technology, not sure how true that info is though).
the buffalo linktheather is my first device in the network media zone, so I have no experience with competitor products.
take a look at the current frequency of the firmware updates on the buffalotech Support -> Downloads page. I would say the frequency is very low compared to the number of problems the unit has or competitive updates that it needs.
the rest of the questions are too technical for me, so can't help on those.
Conclusion:
I'd have to say that Buffalo Online Support through these forums is the worst I have ever encountered in terms of speed of reply (if any). I'm certain I will not be purchasing another buffalo product in the future especially that there are so many similar technological alternatives out there, so it is really the service that makes the difference in this case. Granted that most others might have the same crappy support, but at least i'll be trying something new in the hopes that it might be the one I'm looking for instead of sticking to the same "confirmed" inadequate one.
P.S: I'm basing my above comments about the service on posts I have started in these forums due to problems I have faced with a couple of buffalo items that I bought as a kit of 3 (LinkStation Live, LinkTheater LAN, Wireless N Router). In one of the items, I have been struggling with a problem since 17 days with no solution in sight ...