If I remember correctly it took 6 hours to download a 30 megabyte file when I had a modem.
And I thought I had slow dial-up, was only 10mb per hour for mine.
Speakin of which, should really get Half-Life2 beaten before I get tempted to buy the trilogy-episode expansion.
[EDIT] Any word on whether or not there'll be a boxed-release? I prefer not to have to blow my bandwidth on something I'll be installing on two systems without means of using CD-Rs.