And then there is the fact that your private key is in files, which risk being lost. If you use a keyserver, you have to go find a keyserver to use. Also, some people (myself included) like to have multiple identities, hence multiple publick keys.
It's hell to manage for us hackers, what more your SixPack Joe who has never even touched a command prompt in his life.
What I want to see is something truly unintrusive to use. I like OS X's keychain concept, but I cannot ever bring myself to trust keychain with my private keys.
p/s: I have a public key in my blog. Guess how many times I've received an encrypted email from my blog enquiry? Zero. Everyone uses plaintext instead.
By the way, the public key on your blog is not very copy and paste friendly - I had to redo the armoring.
But yeah, it is no where near as easy at it should be.