Home Theater Mag tested 61 High Definition TV sets (2006 model year) and determined that the large majority of them couldn’t even pass basic competency and capability tests. 54% failed a basic deinterlacing test, 80% were unable to properly detect 3:2 cadence, and all but one of the sets tested had attenuated the bandwidth of the signal to some extent.

But what does all this mean?
Deinterlacing:

“Some TVs take every one of the 1,080 interlaced lines and convert them to a progressive signal. This process is known as deinterlacing. It compensates for any motion in the image and sends it to the screen at its native resolution. Other HDTVs may take a cheaper shortcut and simply upconvert each single 540-line field. The latter process can result in a loss of up to 50 percent of the image’s resolution (for a 1080p display).”

3:2 Cadence Detection:

“Many scripted television and all film-based movies that telecast in 1080i HD are recorded at 24 frames per second. For broadcast, this is converted from film or 1080p/24 video to 1080i/30 using a telecine conversion. A good internal processor should use a method called HD inverse telecine to recognize like frames and reconstruct them for a 60-frame-per-second display using a 3:2 cadence.”

“Without HD inverse telecine, the television’s processor may discard up to half of the image resolution (prior to conversion in 720p displays) during horizontal pans.”

Read on for full charts with all the results.
(Via HD4NDS)