I don't think so. The Panasonic web site shows the ET5 shipping with polarized 3D glasses whereas these are active shutter. I've never seen a TV that would do both types of 3D. They also don't show up on the accessories list for the ET5 and Panasonic is pretty good about keeping their sit up to date.
My TV is not internet enabled, as my apple TV and Sony bluray is, so I couldn't see the advantage. The glasses work fine without any download required for my arrangement. We really enjoy the 3D when we want to use it. It has restored my pleasure in new movies. We had pretty much stopped watching much regular stuff.
The Vt50 has the best picture this year (2012), along with new 3D techonolgy, with much fewer DOA's than Samsung. No I'm not emailing them! It is a great product fairly advertising box content, with great reviews.