An update to Yosemite has just been released. 10.10.3 is now the oficial current version of OSX. This update is intended to address a number of thorny issues outstanding with the operation of the OS.
WIFI was one of the major things tackled in this release. People were reporting a number of problems with their network connections from the ability to connect, stay connected and run at a reasonable speed for this OS.
This release appears to have addressed many of those problems and for that reason alone it is worth upgrading.
Stability and Performance
Both stability and performance isues at a broader level have been addressed by this OS release. Some of the annoying performance issues such as the need to double login or more so have been addressed.
I have not had enough time to work with the product to see how well it addresses these issues other than to do a cursory overview however, I feel that this is more than a worthwhiled upgrade that everyone should be making that is running Yosemite.