This whole things just reeks of desperation on the part of Opera. While Firefox has gained a large market share (i.e. 20%+) and other browsers like Safari have steadily increased their usage Opera has just stagnated the whole time with a pitifully low market share rate amongst all web browsers. According to a few sets of results I found on Google they suggest that even Chrome (which has been in the market for under a year) has a higher market share than Opera. They surely aren't trying to blame all their troubles on poor old Microsoft?!
Here is the actual blog post
from Microsoft explaining how things will work.
It's rather surprising to see Microsoft willingly do this. It's also amusing to see Opera dead last in that screenshot from Microsoft.
UserAgent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1) Gecko/20090624 Firefox/3.5 (.NET CLR 3.5.30729)
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