The facile answer is that Metcalfe's law took effect with FriendFeed here in Italy, as it did with Orkut in Brazil and India, and hi5 in Central America - there's a big enough critical mass of users of the service in the country for other users in the same country to get value from it, and the effect is self re-enforcing.
However, there are clearly cultural factors at play - in Italy, FriendFeed has become an extension of the blogosphere, a place where you can share thoughts and content using more than just 140 characters (which is useful if you're speaking Italian) - a community where you can find professionals, creatives, artists, blogstars or just normal people who want to engage, sometimes arguing but in the end adding value to the conversation.
If you're just looking at certain data then FriendFeed is not a big deal, even in Italy, with Facebook being a much larger phenomenon. But if you're searching for high-quality interactions and you want to listen, understand, gather insights or connect like minded people to produce ideas or crowdsource a project, then it is the right place.
Anyway, you shouldn't just take my word for it. I asked Livefast, one of the most influential and controversial bloggers here in Italy and a FriendFeed rockstar, for his point of view. Here's what he said:
I think Friendfeed became so (relatively) popular in Italy because it was adopted very early by the previously existing – very strong – community of local mainstream bloggers. This attracted (and still attracts) a number of their readers. The Italian friendfeedosphere (or whatever it's called) resembles a lot the Italian blogosphere: same people, same main influencers, largely the same subjects dealt with and the same kind of snobbish attitude.
The reason why *I* prefer it to Facebook, however, is different. I like FriendFeed because my contacts there are all people that for some reason I chose: because I like them, because I dig what they say, because I love to argue with them, whatever. My contacts on Facebook, on the contrary, also include a large number of people that just "happened" to me: schoolmates, work acquaintances, relatives and so on, all people I don't care discussing much with, I don't like (anymore) the company of and, in general, I don't wish to share much of my life and opinions with.
Of course, I'm aware I'm on the losing side. Facebook rules and will soon own the planet (for one thing, it already owns FriendFeed), however, and as long as it lasts, I'm going to enjoy every tiny bit of it.