I have a feeling that they send these e-mails alphabetically by address. For instance, one of my addresses begins with sa and another with st and the sa one always gets the e-mail before the st.
Awww, give 'em a break. They're busy shipping Tiger out to (most of) us, and defending themselves against frivolous lawsuits!
When they first started doing Tuesday updates, I used to frequently get them on Wednesday or Thursday...I remember it took them some time to iron that out. Maybe they should just find a way to take the Tuesday out, and let it be a mythological component in the aura of iTMS, like Tuesday system upgrades are among us mac geeks.