July 4th, 2007 is a Wednesday. So, which weekend is the "holiday weekend", 6/29 - 7/1 or 7/6 - 7/8?? Online and real-world opinion that I've surveyed is right about 50-50. Kinda makes it hard to plan something when you don't know when exactly the traffic will be bad.
I kind of old and such. I remember when a "holiday" fell on the day it fell on and three day weekends were unheard of. For me July 4th is a celebration of the founding of my country. I also do crazy stuff like attend the Memorial Day service at the cemetary to honor our military. I sympathize with needing time off but does it matter which weekend it is. But to answer your question, the previous Saturday is June 30 so I vote for the wekend after.
In Canada, the trend over the past 18 months or so has been watching all the high speed ISPs develop caps - be it bit caps, or bandwidth transfer caps... I work for Bell Sympatico, and we were the first major ISP to be doing so.