I remember a while back someone mentioning that Plasma was pretty much the future of HDTV
OLEDs are the future of HDTV, they have all of the strengths of LCDs and Plasmas without the weaknesses each tech suffers from.
as LCD's couldn't go any further than they currently had gotten.
In terms of IQ, LCDs aren't going much further then XBR8s, but most LCDs aren't remotely close to that level yet. 3D TVs are going to start getting a big push this year, at the moment LCDs are looking like they will have a decisive advantage in that aspect.
are there things that LCD's are better at than plasma's, and vice versa?
LCDs are better in any setting with large amounts of ambient light. When compared to lower end plasmas LCDs don't induce headaches due to refresh rate issues. At the highest end of the spectrum the Kuros edges out the XBR8 for IQ, but the differences are quite small. You can flip LCDs around as much as you want without worry, may sound like a minor issue but I have seen more then a couple plasmas destroyed because they weren't moved properly(you can not tip them too much). LCDs are rather easily superior in terms of power useage and can be quite a bit slimmer then plasmas. LCDs have no issues with image retention or burn in(which have improved with plasmas, but haven't gone away).
Plasmas are much, much cheaper to get a decent display. While the XBR8 is superior to most plasmas, its' cost is significantly higher(~$4K for a 50") then very good quality plasmas(although it isn't out of line with what the Kuros was selling for). A $1K plasma display on average will wipe the floor with a LCD in terms of contrast, killing them in black levels and eliminating the lag that can be seen on some LCDs while offering better colors most of the time. Plasmas have no issues with viewing angles and do not suffer from issues revolving around back lighting(bleeding, uniformity etc).
I'd say in a realistic assesment the biggest advantage plasmas have over LCDs is cost- but this ends up being a big advantage in a lot of other areas. Without local dimming tri color LED backlighting LCDs aren't competitive with plasmas on an IQ basis, and local dimming tri color LED backlighting more then doubles the price of the display. LCDs biggest advanatege over plasmas is there superiority with high amounts of ambient light(although curtains can take care of that for a lot less then the premium LCDs need to overcome their obstacle).