If there is no 5D3 on friday... which I really hope there is... 
I wouldn't spend the allocated funds for anything else because the 5D3 is bound to be released sometime in the very near future if not on friday. I do really want to pick up the 14mm f/2.8L II but it can wait until I secure a 5D3. If you choose to satisfy your need to buy something now, you will likely regret it in the future when the item you really want becomes available and you have already spent the money on something less rewarding. Just my $0.02 in buyers rationale.
I agree that it's bound to come out soon and that makes the decision a bit rough, I don't think I'd regret buying a lens though, as I was going to buy it with the 5D3 until the 3500 price got pretty solid. Time will tell...
No offense, but this is the type of logic that gets people in debt.
And - possibly more important - is what causes buyer's remorse and general disgruntlement about what they do buy, when they realise that they really should have waited...
I agree that buyers remorse comes when you decide you can't get something so you just go and spend your money, but when you move from number 1 to number 2 on the "to buy" list I don't think it's quite as bad. But you're all right, I've waited on a 5D for a little over a year, I may as well just hunker down and keep saving. Maybe I'll be able to afford the camera and a lens together when it's finally available.