Just briefly, the whole feel of the old version (2.5.3) is friendlier and quicker. The "BUZZ" feature has been added, similar to the Windows version, but you are stuck with the stock sound, unless you provide your own sounds - but not only this, you can no longer customise the existing sounds for friend coming online / message receive etc. whereas this was quickly and easily done on the old version, A step backwards.
On the old version the font appearance could be quickly changed from the dashboard, but no you have to wade thru a menu, and the change wont take effect until you sign out and back in. Another step backward.
I was hoping we were going to see some worthwhile improvements, like the incorporation of the drawing pad featured in the windows version which can be a lot of fun. Or the inclusion of audibles, and certainly the fixing of the bug which causes avatars not to be displayed correctly??

But no .. nothing wothwhile here .. Im sticking with the old version until something enticing comes along