The decision to shell out another $130 for the 3G connection is not so clear as it was a year ago. Now that the iPhone has a tethering and WiFi hotspot plan ($20 a month with AT&T), you may want to skip the 3G antenna and instead use your phone to get the iPad online. Doing so has its plusses and minuses:

It lets you save $130 on the purchase price;
It lets you save the extra monthly charge for iPad data (when active);
It saves you some battery life;
The GPS antenna is only on the 3G iPad so you’ll be without it on a WiFi-only iPad;
It requires you to always have your iPhone or other MiFi type device with you, charged, and turned on to get the iPad online. If you are using it a lot, it may challenge your iPhone battery life;
Going this way assumes you will always have that hotspot data connection for the life of the iPad.

I think at the end of the day it comes down to saved money versus convenience.

If you do go with a 3G iPad 2, give some thought to your carrier. Since you can now elect to get a Verizon or AT&T iPad, I recommend you get the opposite of your phone carrier. That way if you can’t get a signal on the phone, you may have a chance on the iPad.