Interesting fastweb, but mumsnet does not equate to youtube, twitter or facebook
Those are used as widely known examples of how a site that depends on user created content can increase/accelerate user participatiom.
Pleanty of discussion type coummunities use a vairety of widgets to the same end.
I prefer the cleaner, streamlined, "each post stands and falls onits own merits based on what those can be arsed to respond think" set up that mumsnet has now, but what I like may not be the best business/techy model for mumsnet when it comes to maintaining thier postion at the top of the pile.
I'm fine to let the people who day in day out have to think about boring things like traffic conversions, stats on page impressions generated by active V non active members, bandwidth and ad revenues have a trial that I can remain oblivious to.
Especially if that is what it takes to give Da Management the room and scope to test something out to see if they can future proof their income, so they don't get tempted to flog it to Blank Faced corperate types further on down the line as a safer bet.
I happen to think the informal, personal interaction with the people running the site is a big part of what gives mumsnet its flavour and personally some widget running in the background that I chose to ignore is a very small price to pay to help make sure some new whippersnapper of a site doesn't suddenly loom on the horizon and catch mumsnet on the hop by stealing all the less active traffic leaving them looking at a merger or a cetain death.