This may not be too bad...
While data in my area (Chicago) has been really pretty damn good for a few months now, the voice drops persist. I absolutely agree they've dropped the ball on this and have to fix it.
Now, talking about HSPA+ specifically, this is possibly a pretty big decision for AT&T and deserves some scrutiny.
Throughout the UMTS world, operators are making the decision whether or not to go to HSPA+ and it's higher throughput speeds, or make the plunge and go with LTE. There are many operators who are going to upgrade what they have and wait out the initial phases of LTE.
There are decent reasons for doing so. LTE is a new network architecture and a new (for UMTS operators) RF technology as well. That's two new things at the same time, which the (very) conservative telecom industry frowns upon.
I could see a situation whereby AT&T decided that since their backhaul is being upgraded, to leverage that newly upgraded backhaul (this is still underway - I'm not intending to say it's anywhere near complete) and add HSPA+. It's a less risky move than going to LTE. There are rumblings that Verizon is having some growing pains with LTE, while this is to be expected to a large extent, it's also something that AT&T can sidestep for the time being. HSPA+ isn't new, it's been deployed in many places already and I suspect most of the bugs have been ironed out already.
This also means that there are a lot of existing and forthcoming mobiles that support or will be supporting HSPA+. This isn't true for LTE at the moment. Yes, everyone expects this to be fixed and for LTE mobiles to come dropping down from heaven, but it's going to be a while. Same for chipsets.
I suspect that this may well mean that Apple will be going the HSPA+ route, which - at least for the time being - opens up a significant speed gap between AT&T and Verizon. 14.4 Mbps (peak, theoretical) vs. 3.0 Mbps (peak, theoretical) is not something to sniffle at. HSPA+ does have a speed roadmap that goes up to something like 85 Mbps, so keep that in mind as well. You do have to deploy more antennas for MIMO to get to those speeds though. That's something I have a hard time believing that AT&T will do, but they could.
AT&T, fix your voice drops, get the backhaul upgrades in, deploy HSPA+ in a meaningful way (e.g., not just for press coverage), and things may indeed be decent for the next 12-18 months. Then Verizon will have LTE deployed and running well, and the battle begins all over again.
It's a short window of opportunity, but it's there.