For 120Hz computer monitors, there's also the
Eizo FG2421, which uses a 120Hz VA panel. But at £450, it's a bit pricy for a 24". But atm it's apparently the only consumer-grade monitor with a 120Hz VA panel. But if you're patient, I'd wager other manufacturers would be eager to jump along and bring their own offerings in the near future, so here's to hoping for lower prices.
== The rest of the post is focused on HDTV talk, so anyone not interested in that can skip to the end ==
Pretty much a rule of thumb for LCD HDTVs:
Samsung uses VA.
LG uses IPS.
The rest have a more mixed selection, so no clear rule for them. Furthermore, most of the bigger names also have plasma and OLED offerings, in addition to their LCDs.
And not so long ago, there used to be TVs with TN panels, too (especially smaller ones), but nowadays TN is relatively rare in TVs. Might find some from the no-name-brands. (I think I read somewhere that some cheaper 4k TVs might opt to use TN to reduce costs...?)
With regards to 120Hz:
There are plenty of 100/120Hz TVs available (VA/IPS). Unfortunately, it's usually limited to only a 60Hz input via the inner electronics, as the source material is pretty much always 60Hz, so no need to enable higher. Computers are the main source for higher Hz material. Although, there are
unofficial work-arounds to unlock the higher framerates, but it's not guaranteed to work.
But even more unfortunately, none of the manufacturers state which monitor uses which panel. Even it they advertise "100Hz", it's most probably just a motion interpolation feature, using a regular 60Hz panel. Some of the "motion" features might not even interpolate anything, they're just inserting black frames or strobing the backlight (which might be good for reducing motion blur, though). I think one old Philips HDTV advertised "400Hz PMR" (PMR = Perfect Motion Rate"), which in the end used a regular 60Hz panel, the rest was just "enhancements". And it's not just a single manufacturer, the whole TV market is full of shady advertising, you really have to dig up if you want to know something specific.