To say that the 50PZ850T is an oddity in feature terms would be an understatement. Obviously the stars of the show - on paper at least - are the set's active 3D and PenTouch functionality. Both of which need more explanation.
If you're wondering why LG has used an active 3D system on the 50PZ850T in direct opposition to LG's virulent belief that the passive 3D technology now used on all of its LCD TVs is the best 3D option, it's because apparently plasma technology - or at least, LG's plasma technology - isn't capable of outputting enough brightness to counter the impact of the passive 3D filter.
Given LG's generosity when it comes to giving away passive 3D glasses with its passive TVs, it's a shame if hardly a surprise that you get just a solitary pair of active shutter glasses with the 50PZ850T.
As for the PenTouch feature, its response time is said to be only 150ms, and its touch resolution is a respectable 4.6mm(h) x 2.3mm(v). It also must be stressed that the feature doesn't just let you draw pictures on the TV's screen; the 'pen' can, among other things, also be used to access and navigate the Internet, browse 'sweep'-style through the photos you might have stored on a PC, or access and write notes for a provided Family Diary feature.
However, within about 10 minutes of using PenTouch, it's looking like quite possibly the single most pointless feature ever added to a TV. Seriously, who in their right mind - aside, possibly, from a toddler - would really want to put down their laptop or tablet computer, stand up, wander over to their TV and start using a huge pen to draw on their TV or use it to access a few cumbersome 'apps' that would be much better suited to a computer anyway?
As for the possible toddler attraction, would you really want your kid to be a) standing literally inches away from a 50-inch TV, and b) banging a pen against it with the sort of gusto that only a toddler can manage? Surely not.
To be honest the feature isn't even something you will necessarily try once and then forget, as it's quite a faff to get up and running, at least to its full extent. So really, highlight feature or not, the best thing to do with PenTouch is forget it's even there and move swiftly on - while trying desperately to ignore the fact that presumably you have to pay a few quid for it...
Rather more likely to appeal to the readers of this website - or anyone normal - is the TV's impressive suite of picture adjustments. As usual with LG plasmas, the 50PZ850T comes with the endorsements of both THX and and the Imaging Science Foundation (ISF) - endorsements that are only handed out to TVs deemed to have enough picture flexibility to be professionally calibrated.
The endorsements also mean the TV enjoys two THX presets (one for a 'Cinema' and one for a 'Bright Room') and two ISF Expert modes, via which you can access in-depth tools like a colour management system, white balance adjustment, and gamma controls.
The 50PZ850T's connections are promising. There are three HDMIs for 3D and HD sources (one less than might, perhaps, have been ideal), as well as a USB port that can be used for playing back a decent variety of music, video and photo files. There's also a LAN port, though it was surprising to find that while this permits networking with other computers, it doesn't also provide access to LG's latest Smart TV online service.
The design of the 50PZ850T has to class as a significant feature, meanwhile. For as well as boasting one of LG's impressively slender 'Razor Frame' bezels, it enjoys a shiny metallic finish that's quite new for LG and gives the set a pleasingly distinctive and gently opulent appearance.
It's worth adding too that the screen enjoys 'Protective Skin Glass', which LG claims boosts picture clarity as well as improving the screen's durability and safety to cope with the fact that you're supposed to be jabbing pens at it all the time.
Finally the 50PZ850T boasts LG's 3D XD Engine video processing system, which actually works to improve both 2D and 3D picture quality as well as powering the set's solid - but certainly not spectacular - 2D-to-3D conversion system.