Terrible update. DO NOT INSTALL.
We lost duplex ability on our main Brother HL-5280DW laser printer after this update (as everyone apparently did).
If you do/did install it, the fix is easy: Go to the Brother site, download the driver software for your printer and OS, install it. (I deleted the Brother laser printer before I installed the Brother driver, but others had reported success without performing this step.)
Then, just add your printer in the System Preferences "Print & Scan" pane. All will be well.
Do not allow Software Update to install 2.8 again ...from reports, it will try to do so.