Opera 9.5, or Kestrel, has been released. Finally, I might add. Peregrine is next, hopefully a little sooner.
Kestrel, has a bunch of improvements over Merlin (Opera 9.0) which you can read in the changelog. Full Selectors support, overflow-x, overflow-y, text-shadow, getElementsByClassName(), window.ononline, <canvas> ImageData, global tabindex, getClientRects & all, and so much more. Performance should be better too.
If you encounter some issue, you can report it using the Bug Report Wizard.