Upload & Sell: Off
I think he's saying that the everything in the HDA (the metal "tub" that houses the platters, etc.) is pretty much the same as previous generations and the big change has been on the electronics on the card on the bottom of the drive. I worked in the hard drive industry for 7+ years, and I generally agree with that. The rise of DVR's and similar devices plus things like NAS boxes in the home have almost certainly improved reliability - those things run 24x7x365 and carry a lot of down-stream cost if they fail (e.g. the labor/service cost for Time Warner to replace the drive matters more to them than the drive itself).
That kind of reliability isn't free or easy, especially when we're packing so much stuff on every platter (areal density is putting 1TB drives in laptops in a 9.5mm package!). I'd say there is probably somewhat more risk to certain types of data issues just due to the precision needed to access data and the kinds of loads people are putting on these things, and some higher impact to manufacturing tolerance issues as well as things like contaminants inside the sealed HDA. But on a percentage basis, it is almost certainly true that drives are more reliable today than ever.
It is also true that different vendors have different quality rates, and the differences even between product lines from one vendor can be significant. My data is old, but generally I trust most stuff from Hitachi, the non-consumer end of the Seagate line and pretty much anything from Samsung (who is completing the sale of their hard drive division as we speak). My distrust of WD (among others) comes from data so old that it is silly, but I won't buy outside of the three brands I mentioned, and I generally lean toward their higher lines meant for entry servers and workstations.
The change in warranty probably has as much to do with the flooding and protecting the bottom line while revenue is scarce as anything - one of those things executives have debated for years but nobody wanted to be the first one to do it. I doubt we'll ever see them go back on the consumer lines.