typical timeframe for sending out holiday invitations?

What's the usual timeframe of sending out invitations for a Christmas party? Is 6 weeks good enough?

I want to have our friends save the date for our annual Christmas party, since December fills up so fast, but don't want to be TOO early with this since it's not too formal

We were talking about the same thing this weekend. I am curious to hear what everyone else thinks

oh, and on that same note, I want to design my own Christmas invitations, have them printed and shipped to me, but the only website I know of that does this is Shutterfly.
Since I don't want to use a photo this doesn't help me. Anyone have any other sites?

Thanks!

Teri - do you have Photoshop? If so, you can custom design your own invite in Photoshop and then have Kinko's print them for you. Or, there's a great site called CardStore.com that you upload your artwork to, and they will print, address and stamp all your invites for you!