The Kokua Viewer keeps improving for use on OpenSim grids, while keeping up with the latest code revisions and bug fixes from the SecondLife viewer.
Release 3.7.27.35441 brings Kokua to Second Life version 3.7.27, a Maintenance Release cohort, 3.7.26 Hoover Height cohort, and to RLV version 2.9.9. In addition a number of small issues for usability on grids with currency enabled and upload fees have been corrected. The update will also fix issues for the Linux viewer such as for flash playback and compatibility with webkit.
The update also includes the Hover Height Improvements Linden lab published in March.
The full details are in the Kokua/Imprudence Blog where you also can find download links and the full release notes.
This is a recommended update and possibly the best viewer you can choose as a Mac user in OS X 10.10 (Yosemite) on OpenSim.