Hanging a plasma tv question

[chili]

I have a 50" panasonic plasma 3d tv, doe anyone know if i were to hang it on a wall what kind of height should be the best for viewing?

wall Bog standard size wall bog standard size sofa. if you were hanging this what height would you have the baseline of the tv from the floor?

cheers

 

[chili]

Nice piccys the door handle gives me a reference point to play around

Cheers

 

[chili]

God give me strength

many thanks for the answers and tips, i too think my tv should be eye level however "the wife" seems to think not, also the wife did not consider the sky box or bluray player location. So for now its staying where it is