27" LED LCD is due 2010 from LG and Samsung so 27" will be the size it comes in not 28". You will be able to get these in 2010, perhaps early in the year if all goes well.
There are other LED LCDs on the market such as Lacie at the 30" size range as well as a Sony Bravia model. It seems from what I see, the sizes are 27" then the next size up is 30" for LED LCD for 2010.