Intuit released the QuickBooks 2013 R14 update for the U.S. version of QuickBooks. This is available as a manual update from the Intuit support website, and probably is already out as an automatic update. I’m not sure when this was actually released, you may already have it now! I don’t have any information on non-U.S. versions.
This is the first update for the 2013 desktop product since January 2014, so it looks as though Intuit believes this is pretty stable now. I’m going to guess that this is the last update we’ll see for this year of QuickBooks, as it will probably be retired next May. Note that in the US version they skipped “R13”. That usually happens when they have a non-US release for some reason, that doesn’t need to be released in the US.
There is only one change in this release, and I can’t really comment much on the impact of this. Intuit has updated the “Auth ID and Realm ID” to be 64 bit values in the database, which helps support “more users and company files”. I don’t believe that this means that there is a change in how many users you can have in your desktop product itself, I believe it has to do with your Intuit online account, which you use to manage things like your TurboTax account, QuickBooks Payments, ProAdvisor account (if you are a registered QuickBooks ProAdvisor), and so forth. There should be little impact for most users, I would guess.
Update 12/11/2015: Intuit has pulled this release off the shelf, the currently available one is rolled back to the R12 release. I don’t have any details on why this was done. I believe that a problems was found that might affect some users, so they have stopped distribution. Given what the update involves, I don’t think that the majority of users who may have upgraded will have any concerns.