However, it’ll now be replaced by a running upgrade which means that there wouldn’t be an announcement or anything. AMD will simply start shipping cards with the new Tahiti XTL chip and only way to tell these apart from the Tahiti XT2 based ones will be by looking at the BIOS of the card.
the Tahiti XT2 chip in the R9 280X will be soon replaced with the improved Tahiti XTL chip which will lower the power consumption and run cooler.
AMD seems to be on a roll. First R9 290X, then the R9 290 (which is expected to be equally good) and now the R9 280X is getting an upgrade.