Some retailers are out of stock for the Thunderbolt Display, suggesting that the 27-inch monitor could be upgraded, perhaps gaining a slimmer design like the last iMac. As pointed out by the AppleInsider, Amazon, MacMall and J & R are just a few examples of large resellers (outside) who are out of Apple monitor stock.
In fact, the product needs an upgrade, as it still has USB 2.0 ports. Not to mention that if the iMac (which a complete computer) got that thin, imagine the Thunderbolt Display, which is just a monitor! Amazon says that the product will be back in stock at the end of the month (1/26), so we will see if it even paints anything new. It remains to be seen whether the alleged problems of producing iMacs will allow the company to produce screens for the Thunderbolt Display at the same time.
Now, one thing I would really like to see was Apple offering more size options, such as a 21.5 inch display (following the iMacs) and a larger one, 30 or more inches. But I think that hardly happens.