I don't know how I feel about a Friday night launch. On the one hand the weekend allows for fixing problems, but on the other hand they are doing a webcast and have been building publicity for more than a month.
Fridays are almost bad as nobody will remember you next monday.
Thursdays gives you just one more day to digest your offering.
Now you have mondays, tuesdays or wednesdays left.
Mondays are catch-up days, everybody getting up to the minute with meetings, planning, late tasks, errands, etc.
Wednesdays are good, very good, but no better than tuesdays, which gives you three more days for penetration, attention, conversation and full digestion.
So, even if wednesdays are good, tuesdays are better.