Joe Brinkman has announced the release of 5.3.1 here.    This replaces 5.3.0, released and then withdrawn last week.  Given the problems with 5.3.0 and the complaints from some that there are other issues, particularly for those who use alternative registration systems, I'm going to cautious and give this version a few days before thinking about upgrading.

On that subject, an email from PowerDNN today has this advice: "While DotNetNuke 5.3.1 will fix a large number of bugs, unless you are on 5.3.0 or are being impacted by one of the bugs, there is no major reason to upgrade at this time."