I've always wanted a big screen but have held onto my little TV for so long putting most of my money into camera gear. Now my wife has asked me to look into buying a TV.

In Japan, the 3D TV's seem to be all the big stores are selling. Smaller stores are still selling the 2D only TV's and at a very reasonable price (I think). A Panasonic 52 plasma (Last years model) is going for 2000USD where the 3D version is almost double. Since I have my old TV I am able to trade it in for a 300USD discount with most stores. The 3D TV in 2D looks the same as the simple 2D...I'm wondering if it's worth the extra bit for content that will be coming out over the next couple of years.

I've seen the LCD vs. Plasma debate. The store clerk says that if I do any gaming that has a picture that remains on the screen that the 'burn in' issue is still there. True? LCD are great for gaming but not so good for 3D since you have to be looking straight ahead. The Sony 3D TV's are a bit cheaper and their biggest 2D TV's right now are 46 inches. Nothing bigger is being sold, at least not in the big stores.

So, can someone point me in the right direction?

...Now my wife has asked me to look into buying a TV...So, can someone point me in the right direction?

It sounds to me like you married the right person, so you're already pointed in the right direction. ;-)

Seriously though...

3D
I'd forget 3D for the time being. What compelling content is there? Do you know whether or not you and your wife can watch 3D without adverse physical effects (headaches, etc.). If you really want 3D, I'd wait until there is more compelling content...the good thing about that strategy is that if history is any guide, prices will drop while you wait.

LCD v plasma
Burn-in is still an issue with plasma, though less so with current technology.

There are some very good LCD HDTV's available that have larger field of view. IMO, plasmas still have a better picture from larger side angle. What is the largest typical viewing angle in the viewing room/s? If you expect viewing to occur from the side (i.e., HDTV in a room used for parties or gatherings), you would probably prefer plasma.

Another consideration between LCD and plasma is ambient lighting. Plasma screens tend to reflect light from windows and lamps in a way that is more distracting than LCD screens. Again, what is the lighting situation in your viewing room/s? If you have windows (day) or lights (evening) that would reflect off of the HDTV, you might prefer LCD.

It's all about compromise.