As far as I know Sony will honor the warranty. Call Sony and discuss it with them directly, that's what I did. In fact, you can add an extended service plan directly from Sony...
You may want to visit sonystyle,com and look into an extended warranty through Sony. They are competitively priced and Sony allows you 60 days from purchase to add the warranty. I purchased mine (60" SXRD) from an online retailer and was nervous as he!!...but the $700 difference was too hard to pass up. I was able to purchase the TV and the 5 year extended service plan (warranty) directly from Sony and was still almost $400 under the price any local brick and mortar was quoting me. BTW, I got my SXRD last week and it was a March 06 build and works perfectly. I was expecting an "older" set but everything worked out in the long run.
As to your question about build date, it's prominently displayed on the back of the TV, you can't miss it.
