From now on, Construct 2 releases will be split in to beta (for testing) and stable (already tested) categories. This is to help prevent unanticipated problems in new releases affecting users who don't want to help test Construct 2. For example, r79 had four revisions for various reasons, and this is unacceptable for users who just want to work on their projects without testing new features. Every Construct 2 release so far has been "beta" and therefore has been implicitly for testing, but now we feel Construct 2 is mature enough that not everyone who uses it is going to want the bleeding-edge latest features which have not been broadly tested. We do test builds ourselves before release of course, but as a small team we simply do not have the resources to test quite like hundreds of people running it on their own particular software and hardware setups with their own unique usage patterns. Real-world beta testing is incredibly important to help make Construct 2 as reliable as possible.
So we do encourage you to try beta releases. You'll be the first to get new features, changes, fixes and optimisations, but the flip side is beta releases are more likely to introduce new problems too. If you have important projects you want to get done with minimum fuss, stick to the stable releases and it's far less likely you'll experience new problems, since the releases will have already been tested by beta users. Either way, as always we highly recommend staying up to date with whichever branch you choose, since we're constantly improving Construct 2.
On startup, you'll be prompted to choose your update preference. You can change it at any time in the Preferences dialog
Also new this build is integrated backup. We strongly recommend using this to set up a daily backup to a Dropbox folder to ensure your work is safe. We regularly hear about people losing work on the forums due to computer crashes, hardware failure or other disasters. Don't be one of them! With Construct 2's built-in backup features there should be no excuse for this any more - you just need to set it up once and then it will work automatically without intervention from then on. We cannot stress enough how important this is. For more information please read the new tutorial: Keep your work safe with Construct 2's backup options. (Please note that since this is a new feature in a beta release, you should double-check Construct 2 is making backups correctly, in case there are bugs in the new backup code.)