If it were "a few years ago", I suspect you're referring to TEMPEST attacks which basically focus on making use of emissions from equipment to collect intelligence.
Such stuff still goes on, but these days there are additional tools at their disposal and technologies which tend do be less fiddly to intercept such as WiFi.
As for LCD, although it certainly greatly reduces your emissions compared to CRT, it certainly doesn't necessarily eliminate them (signals leaking from the video cable, reconstructing reflected and diffused light patterns emitted from the monitor etc..).