As some of you may have read in the recent press release, Opera will be releasing a speech-enabled browser some time soon. As with IBM's release, speech-enabled browsing will only work on Windows 2000+. But for those looking forward to 7.60, don't dispare, there are plenty more nice enhancements on the way.
The initial previews of 7.60 will not have the new IMAP back-end, as previously planned. It is also very likely that 7.6x will not include the new back-end at all. Getting IMAP up to the necessary level has taken longer than expected, but it is still being actively worked on and is a priority. I cannot comment on when users should expect to see the new back-end in a public release.
As for what features and bug fixes will be in 7.60, you'll have to wait and see. :) Initial previews will most likely only be available for Windows.

