piatkow - 5:54 pm on Dec 17, 2012 (gmt 0)
I will go with undated sites. In the music business it is rather useful to know of a gig is next week or two years ago!
A personal pet hate is promotional links to non-public "social network" event pages.
Expect me to sign up for an account just to read your advertisement? Dream on.
One that I would add is, when registering for something with a US site, being required to pick a US state abbreviation when entering a non US address.