Spaetz makes a very good point there. Being a fan of OpenID myself, and having read both the 37signals and the webmonkey articles, I was struck by the extent to which people seem to be misusing OpenID.
If you're trying to remember an OpenID URL of the format http://OddSubdomain.OpenIDProvider.tld/WeirdAccountName, you're doing it wrong. The right way to use it is to have your OpenID as http://my.vanity.domain/ , perhaps appending /openid or some simple string, and from that domain, which you control, nominating your OpenID provider _du jour_, which can - and probably should - change regularly.
This gets rid of the "I forgot my account details with my provider so I got locked out" problem, which seem to be many of the problems in both the articles mentioned above. I have in fact locked myself out of my provider twice, and each time, I found a new provider and switched in minutes, because the OpenID URL I had registered was on a domain under *my* control, not some third party's.
I'm a big fan of OpenID and I'm sorry it won't catch on with most sites, and I'm fairly sure the reason why it won't is, as has been said here already, the benefits are all to me, not to the site owner. I look forward to being able to use it on LWN soon.