So, I don't think I'm really the most qualified person to answer this question, as I don't use Twitter at all (I do understand the potential value of it, but I think the fanaticism surrounding it is beyond silly) and have only recently started to scan FF (sometimes I'm able to pick up a cool link or two with minimal time investment, which is good).

I disagree with the post because it contains over the top sensationalism, misinformation, and trivial matters -- not because I've a FF evangelist like some others noted in the post.

Those things being said, I do think they have a few things going for them (Disclaimer: I was interested in interning there this summer, but had committed to a position by the time they got back to me):

Minus Twitter, they're still supporting 34 other services. (http://friendfeed.com/about/faq#services).

Their team seems pretty strong if you ask me, or anyone with a clue (http://friendfeed.com/about/team).

Some people obviously like the service (http://siteanalytics.compete.com/friendfeed.com/?metric=uv).

There's a few other things but honestly, to me, by and far the strongest point about FF seems to be their vision as a content discovery service (http://mashable.com/2008/03/25/podcast-friendfeed/). They're gathering a lot of data, and while it may not seem very useful or valuable yet, I think when they work it all out, it will really be something special. You might want to read Paul Bucheit's (one of the co-founders of FF + Gmail creator) post on this (http://paulbuchheit.blogspot.com/2008/04/power-of-links-and-...).

To be fair, I do think they have a few things going against them as well:

Out of the box, there's way too much noise on the service right now. Although they've given users fairly good tools to deal with it (Subscriptions, Likes, Hiding, Views, Rooms, etc.), it's still not good/easy enough for most users. I just want to see interesting content without any work or knowledge on my part. Even simple things like sorting by most likes or most comments (or some sort of magic 'ContentRank') would go a long ways. They are working on this, so we'll see how it goes (in the meantime, you could check out http://friendfeedlinks.com/, but it doesn't seem very satisfying to me because it's only for the link/digg entries of FF).

Facebook seems to be trying to get in on this space by integrating external services (http://mashable.com/2008/05/23/facebook-friendfeed/) as well as their upcoming profile re-design: "As part of the redesign, Facebook is dramatically playing up the role of its News Feed" (http://news.cnet.com/8301-10784_3-9949475-7.html). To be fair, they are in slightly different groups (Subscription Model vs. Friend Model - Relatively Open vs. Relatively Closed), but FB still poses a very big threat (not to FF's current user base, who all seem think FB is old and lame, but to their potential future user base).

To get perhaps get a more qualified (though obviously a little biased) perspective of what they have going for them, you might want to check out what some of their users think: http://friendfeed.com/e/cf6b48c8-29d8-11dd-92fc-003048343a40

P.S. You note that when you see widgets on people's blogs, they're twitter loaded. This makes a lot of sense if you think about it, I mean how often do you post photos on Flickr versus sending out a tweet? Again, this is an issue with noise. You'd probably be way more interested in their non-tweets if only they'd show up.