Conde Nast just released app updates for its April issues of Conde Nast Traveler, GQ and Wired (and updated the Vogue app days ago) to adjust to the higher-resolution image display in the latest iPad. Back issues will still have lower-res images, though, which some are complaining about.
"The way publishers are adjusting is bound to be controversial, as well: upping the file sizes of their digital editions by changing from .png files to .pdf," according to Talking New Media. "The change, though, will certainly lead to better looking magazines. Whether publishers and vendors can increase download times to compensate will be one [of] the challenges that must be faced."