I recently bought a new Samsung 32" 720p for the bedroom. It was only $50 more than the Vizio next to it, but had a clearly superior picture (SD and HD).
That being said, Vizio TVs will be what gets the bulk of US consumers to switch over to LCD and HD from their CRT sets. They offer Joe American a decent CRT replacement for a very good value.
Sony sets have always been overpriced for what you get, IMO, except for the old Trinitron CRTs. It is all about the panel. There are companies out there who charge based upon their name and could easily be using a panel that a no-name brand is using, with an equal picture. Actually Samsung and Sony often use the same panel as well (a few years ago they opened an LCD plant together), but you'll usually find the Samsung quite a bit cheaper than the equivalent Sony. Although Samsung is not an off-brand, they don't seem to over-charge just because their name is attached like Sony does.
In the end, to me when it comes to LCD, if a trusted name brand like Samsung or Toshiba is only $50-100 more for a set over a less known company like Vizio, Westinghouse or Olevia.. I'd go for the Samsung/Toshiba in most cases. But I could easily recommend a Vizio to a first time LCD buyer on a budget, as they do make some very nice affordable LCD sets. Perhaps the Vizio might have a higher chance at failing, but always make sure you check your warranty out as well, before buying a new TV set.. especially with the newer technologies.