As I have previously heard, Opera announce they are moving their rendering engine from Presto to WebKit. I have been a loyal Opera user for some 10 years. I have mixed emotion about this. Opera used to be the most innovative browser among the many. For a few years, it is the only browser that supports tab and zooming. But its market share has remain low. There are always web pages that does not work on Opera. And it has only become more so as web applications get more complex and few people test it on Opera.
Having to develop and maintain your own rendering engine and be compatible in such environment is difficult. I hope this move will allow Opera to live on.