The 4 AA goal zero deal won't even come close to charging an iPad in its own. The panels certainly will, though.
About 3 years ago the 1200 mah AA's were common - and partly why rechargables got the reputation of being weak. These days you can get 2500 mah low self discharge AA's. 2600 normal NiMH batteries can be had for around 1$ each. I found these low self discharge 2200's for a bit over 2$ ea. in a quick search:
http://www.amazon.com/exec/obidos/ASIN/B001OYD7SI/?tag=2ahawaii-20The 4 batteries in the Goal Zero pack just get the voltage up over 5v to charge USB devices so even with 4 batteries you'll only have 2200 mah, or 2.2 amp hours.
An iPad has a 42.5 "watt hour" battery. At 5V that's 10.5 amp hours... or 5 sets of 4 2200 amp hour batteries. Which is ridiculous to think about hauling around.
But solar works best a little differently when you're thinking about charging a device like an iPad. Instead of charging the AA batteries and then using them to charge the device, use the SUN to charge the device. I haven't yet been able to figure out if the Goal Zero battery pack works this way (it looks like it does) but the best scenario is that you put fully charged AA's into the pack and use them as a buffer and voltage regulator while the sun charges your iPad. Works best if the tablet is off but can still be used to extend run time with the tablet on if you need to.
The 7 watt panels would fully charge an iPad in about 10 hours - realistically about 1.5 days of useable sunlight. Assuming you aren't playing Angry Birds for hours on end in your survival scenario, this should be sufficient power using the iPad as a big GPS or an emergency reference manual.
I like 15 watts as a minimum for charging a tablet for light daily use. As with all things solar, though, there really isn't a truly portable, robust, stable and inexpensive solution. You have to match your power use needs to the solar equipment you can afford to pay for and haul.
For example, a really nice portable solar setup would be the Goal Zero Nomad 27. 27 watts in a 3.5 pound package. Add one of the AA power packs and you have a wicked fast AA charger that can also recharge you iPad in about 2 hours. Not cheap - around $350 for the whole setup at the best prices I could find.
Nice thing about it is that 27 watts is applicable to more than just USB charged devices. If you have a base camp with a deep cycle 12v SLA battery for lighting and whatnot, the Nomad 27 would be useable to add some charge to that system, as well. It could also charge up a laptop in about a full day of sun, keep a store of AA's for radios charged up, etc.
Surf: Yup - eneloop batteries are good. They are low self discharge. The problem (and why they are cheaper) is that they are also lower power than other batteries to be had these days. That pack at Costco (which I have and use daily) is 1900 mAh. That's good, actually, but if I can get 2200's or better for the Grab-n-Go setup I would.