Early Monday JD_2020 popped in the WAW Barracks and posted a quick thread about the 1.7 patch being wrapped up and released this week and today is the day!
To kind of put an end to some lingering speculation about Map Pack 4 I think this answers the question as this patch is appears to be just wrapping up some bugs hanging around comes in at only 15.8MB. I could be wrong but I would imagine that this will be the last update for WAW now that the groundbreaking Modern Warfare 2 is released and flourishing and hopefully Treyarch is working on their next COD installment. As long as it is still actually a PC game I will be quite interested!
You can get the patch here on CODV or you can head on over the callofduty.com PC Updates page in the link below and find a boatload of more places to get it.