This is most likely going to save me money. I can see where someone with only 3 phones on their account potentially wouldn't save any money with this, but I have 6 on mine. Because of existing AT&T rules, I can only have up to 5 phones per voice plan. So I currently end up with 2 voice plans.
By the time I'm done, we have the following structure:
$90/month plan w/ 1 additional $10/month phone (1400 minutes, and yes, the people on this plan regularly get close to that)
$70/month plan w/ 1 additional $10/month phone (700 minutes)
5 $30/month unlimited data plans (the average usage per month over the last year being about 1.2GB per month, per user)
1 $25/month 3GB plan
2 $30/month family unlimited texting/mobile-to-any-mobile plans.
Before taxes and add-ons like phone insurance, and my company discount, I currently pay $415/month.
By switching to the new structure it'd look like this (before taxes, add-ons, and discount):
$120 10GB/month plan (including unlimited voice and texting)
6 $30/month phone connection fee
$300/month. I'm going to save $115/month by switching to these plans, and if 10GB/month isn't enough, I can upgrade to the 15GB/month plan for another $40, and STILL save a bunch.
Is this a good deal for everyone? No. But in my situation, I believe it will be a good deal for my family (yes, everyone on my plan is related to me) of all adults, who are mostly around WiFi, half of whom are power users, and half of whom are normal users.
Also, before anyone pops up with "You should go prepaid!" I looked into going prepaid. While certainly it would work for 1 or 2 of my family members, the coverage for Sprint (which Virgin rides on) is crap in my area, and some of my family regularly travels to Canada, which - the last time i checked - is problematic. Some of that may have changed (certainly not the Sprint coverage - people complain constantly in my office), I admit, but I appear to be one of the few people with AT&T who has never experienced a problem with customer service, coverage, or data speeds.