I've noticed this too. My theory is that Samsung realized consumers were getting mad about not receiving a true Samsung panel and instructed their manufacturers to stop putting their identification letter on the model number. That, or one or more manufacturers simply have no identification letter.
The only other way to know for sure would be to open the bezel up, and find the ID number on the back of the panel itself. This will technically void the warranty but there'll be no physical evidence that you were in there, i.e. not like a PSU that has a sticker going across the opening that you must break in order to get in.
If you're set on the 245BW, my advice is to just go ahead and buy one in-store from ANYWHERE BUT CIRCUIT CITY. At this time of year, you'll be able to return it through January, that's almost two months. At Circuit City, if you can't prove it to be defective, they will try to rape you for a 15% restocking fee, and may do so anyway even if it is defective.
Chances are it will have an ID letter on it, and if not, just use the TLAR method. If you don't think it looks how it should, just take it back for either an exchange or a more solid brand name. Remember, you're the customer, you have every right to do that if you aren't 100% satisfied.
From what I've heard, bad panels have had a strong pink or blue tint.
Here are some links:
Disassembling the Samsung Bezel:
http://www.bcchardware.com/index.php?option=com_content&task=view&id=4259&Itemid=40
In-depth review that acknowledges the use of outsourced panels:
http://andrewswihart.net/blog/review-samsung-226bw-lcd-c-panel