NONTROPPO  Current version is very smooth and functional, and unite is a very welcome additional technology, wonderful for quickly sharing documents without the burden or bandwidth bloat of using mail.

Note also that widgets now run as separate "applications", so can run independently of the browser. Not as useful for OS X users as other platforms due to dashboard, but a better experience overall nevertheless.  
(Version 10.10.6790)

NONTROPPO  Note there have been problems with the auto-update function from previous 10.1 snapshots to this final release. You need to delete your ~/Library/Caches/Opera/ directory then do a manual upgrade to get it working, see this article:

http://my.opera.com/danaleks/blog/2009/11/24/problems-running-1010  
(Version 10.10.6790)

DANA SUTTON  All very nice. BUT in the contract I signed with my ISP I agreed I wouldn't operate a server over the connection. I bet this is s. o. p. in the industry and that pretty much everybody else has signed a similar agreement. And this makes perfectly good sense. When carriers think about "capping" or imposing monthly quotas on bandwidth consumption, they do so in response to the abuse of a small number of bandwidth hogs, with the end result that said hogs make life tougher for everybody else. So I have a problem with somebody distributing a program that facilitates setting up home-brewed servers. In fact I think itÂ’s downright antisocial and potential harmful to the Internet community.   
(Version 10.10.6790)

SYZZYGY  No crashes or issues at all here. This Opera version is smooth, snappy and stable for me so far.

I'm running OS10.5.8.  
(Version 10.10.6790)

ERICG  Quits after a second or two.  
(Version 10.10.6790)

TONY AGUILA  Though not my primary browser, I have always had a copy of Opera installed on my Mac. This particular version exhibits a very bizarre behavior. It will NOT launch when the application is located in the Applications folder. If I move it to the desktop, it will launch properly—be it by double-click, open from the Finder menu, or Open Page With from Safari's Develop menu.

I have also found one particular link (a redirect to YouTube) which crashes Opera (100% repeatable), while that link works fine in Safari and Firefox.

My system: MacPro3,1; 6 gibibytes RAM, Mac OS X 10.6.2 (build 10C540) with 64-bit kernel and extensions.  
(Version 10.10.6790)

KAWAII  Everything good so far, 10.10 is more stable than 10.0 however it is early days; it will be interesting to see how things work out in the next few days/weeks/months.  
(Version 10.10.6790)

MACSOLU  --

Definitely still a work in progress. The Yahoo home page (now "New & Improved" - blech) is very improperly rendered... paragraph/body text is squished to a single character and goes straight down vertically, like this:

T

h

i

s

i

s

s

c

r

e

w

e

d

!  
(Version 10.10.6776)

OZEAN  I wonder when they will enable the new video and audio elements of HTML5? They have offered special builds that include this functionality for quite a while, but support for these elements hasnÂ’t made it into the official release yetÂ…  
(Version 10.10.6670)

MACINEN  Thanks Steven Goodheart and Orion. I found the solution to the problem and still blame Opera: The bookmarks.plist stays gray (not choosable) and the html form from Safari (to the desktop) stays gray too. I have the newest Snow Leopard on MacPro 8-core and I have MBP from this summer. The same thing with the laptop, btw.

The problem was language! Opera is automatically taking finnish as my language (OSX). When I changed Opera's language to english the bookmarks were imported just fine. (Then I had to change back to finnish again and destroy the english prefs). I think this is something they should look at in the Opera-company: importing should work with every language.  
(Version 10.01)