Cap Watkins makes some great points about company character and how it influences users to continue using products (or even come back to them after being burned).
I'm one of those people who deleted my Myspace profile a long time ago, never to return. Their horrid user experience (remember all those terrible Myspace "theme" sites?), combined with the same type of bottom-of-the-barrel users that have infested places like Youtube nowadays, was a huge turnoff after a while.
I honestly don't care what Myspace has done to make the site better since I left. I have no reason to, since everyone I know is on Facebook or Twitter, and I had such a bad experience with it years ago that I'm almost a little surprised that it's even still around.
As for Flickr (also mentioned in the above piece), I'm not one of the people who used it during its heyday. However, I do think that the service still has so much life and potential left in it, if only Yahoo would give it a chance to shine. I personally consider it to be Yahoo's flagship product, even if they don't. There are a lot of people who are heavily invested in the Flickr ecosystem, and there are even people who have met on Flickr and gotten married later.
With an existing hardcore userbase like that, Flickr could definitely make a turnaround in ways that Myspace never will again. Yahoo's company character in the last several years has caused people to label them as doomed, but I believe there is still a spark of hope for them. Especially with Marissa Mayer at the helm.
Anyway, go read the rest of Cap's post, it's great stuff.