Detruire: It may be worth checking the Chorus site from time to time, too. They dug up half our street in Oct/Nov last year, the site said "available" two weeks ago, and I haven't seen the mailer yet.
I didn't get anything in the mail until about a month after I'd had everything connected. Definitely check the Chorus site!
Some ISPs allow you to "pre-register" an address; my street went live a week or two before the map was updated so I was able to get my order in nice and early :)