The easy answer is “eventually, but not yet.”
There is a lot of great press about how El Capitan offers improved performance and stability. Unfortunately upgrading is a contextual decision. Unless you have some super urgent business need for some of the new features (and we don’t mean you want to geek out and play), hold back. Like our previous warnings, new software, including new operating systems, always has bugs, especially when first released. Apple’s current annual release schedule means this has become a regular occurrence this time of year. Depending on the context of your mix of applications, plug-ins, and hardware accessories, your mileage will vary in terms of which bugs you experience.
In order to ensure that your productivity is not interrupted, we strongly encourage you to avoid the El Capitan upgrade until we can work with you to ensure that your environment is completely compatible. Below we have listed applications in several groups; those will not work under El Capitan, and probably never will as the developers’ don’t have any plans to update them, and those that don’t work now, but are reportedly being updated by the developer’s for compatibility. There are also those that are reported as being 100% compatible, but take that with a grain of salt. Please keep in mind that if you upgrade and run into an application that you need regularly that is not compatible, the only option will be to completely erase and rebuild your computer (after backing up your data). Obviously that is expensive in both time and energy and therefore best avoided!
Applications known to not work, or are not supported (read as: you will or may run into issues and there is no avenue for support)
Applications that require testing and/or upgrades before they are compatible (read as: you will need to check the exact version you are running to see if you have the latest compatible patch)
Please note that this is only a sample, and is not meant to be a comprehensive list. In many cases, the upgrade or patch you need will be free, and easy to install. In other cases it won’t. The key takeaway is this is always a contextual decision. There is no “right time” to upgrade. It always depends on your needs, your environment, and your level of tolerance for a few bumps along the way!