Im having a similar dilema, my budgets a little more than yours but just when i decide to go for the Panasonic TX-37LZD800 sony go and release the 37v4500....plus im also interested in the new toshiba as i currently have a 32" tosh regaza and its fantastic!
Now i dont know wether to hang on until i see a review of the sony and toshiba or go ahead and get the panasonic. :(