Retailers trying to replenish their stock of Apple's only normal-sized display are now being told something to the effect of "NO, JESUS CHRIST, NO MORE 20" DISPLAYS, OK?" This, of course, created rumors.
MacRumors points out the most obvious possibility: that Apple is letting current stock dry up to facilitate a transition to new, refreshed 20" displays, with LED backlighting and Mini DisplayPort compatability a la the 24" model. This sounds reasonable, but another possibility—less agreeable—is that Apple's range of displays will contract, leaving the low and high ends at 24" and 30", respectively. If the refresh theory is true, we should know soon enough—a cessation of deliveries, assuming it's to make way for new product, is generally a late indicator. And as far as speculating about a possible round of product updates goes, you really can't ignore yesterday's leaked pictures of the highly perforated probably-Mac-Mini. Interesting timing, at least. [MacRumors]