I just started using my panasonic tc-p50gt50 today and couldn't get my Panasonic (Ty-ew3d3m) glasses to work. These glasses came with the Avatar pack I received with my previous tv. Should they be compatible?
No the previous year's Panasonic 3D glasses used infrared while the 2012 models use bluetooth (RF) so they are incompatible.
However the new 2012 bluetooth 3D glasses models from both Panasonic and Samsung are now compatible with each other's 2012 3D TVs.
The cheapest compatible model with the GT50, is the Samsung SSG-4100GB for under $20 on amazon or at Best Buy stores.