My tv is a plasma and to my knowledge does no upscaling: it says 480p or 576p depending on whether it's an NTSC or PAL source.
Resolution with Plasma is a very knotty issue, the whole "Full HD" thing has been largely pushed by the LCD makers to try and screw Plasma over, it is semi-working as well. Plasma really has no need to "upscale" - as plasma screens do not really have pixels in the same way as an LCD.
The image still looks excellent depending on the quality of the master. I will confess that material filmed in HD does look better on an HDTV, but my film collection is mostly 70s and 80s; I fail to see how HD would improve upon those films other than showing me more grain than I already see; hence my lack of interest in the current HD media.
Well, it does depend on the quality of the master but a really well cleaned up bit of film has an incredible amount of information that can benefit HD. The Star Wars trilogy looked stunning when cleaned up for DVD and doubtless would look pretty stunning on HD as well. Whether such effort would also be applied to other releases, well, hopefully quite a few.
Things which really stand no chance of looking better on HD ever include TNG, DS9 and VGR, filmed on cheap stock, they look pretty poor on DVD.
With regard to upscaling, if the DVD has more information than normally visible on an SDTV, I'll concede the point; if not you're just playing tricks and adding information.
Huh? We are having a discussion this is not the college debating club, I am trying to have a friendly chat about the benefits of an upscaling DVD player not "win" a debate. Frankly there is no debate, the benefits to a quality plasma are pretty minimal.
It may be better than fiddling with the sharpness settings on the TV, but it's still adding information that isn't in the source and I would expect that to have inconsistent results depending upon the source material; as a consequence I would avoid it.
Here there is a debate - the technology that has really helped turn around Home Cinema is DSP, the ability to process sound and pictures and enhance them.
An LCD TV has a set number of pixels to fill, it HAS to upscale, there is absolutely no way it cannot or you would see a little box in the middle of the screen. An upscaling DVD player connected via HDMI returns a better picture on an LCD TV to my eyes than an SD output converted by the TV. The difference is slight. Progressive scan and either a Component or HDMI connection are IMO more important.
With Plasma, as I said earlier, this is somewhat less of an issue. However modern technology really does strongly argue against old purist notions about adding information, as those working in this field have done some amazing work which filters through into even cheap consumer electronics.
