I just switched from an AT&T 32GB to a Wi-Fi only 32GB. I will use my iPhone as the hotspot for my iPad and/or MacBook Pro. Once the new iPhone is released in the coming months, I will upgrade to it and presumably get my 4G data connection that way. One bill, no hassle. Savings up front on the iPad itself, a bit of savings by having only one data plan, and avoiding the dilemma of which carrier to choose at this point in time.
If you think about it, buying a maxed out iPad at almost $900 after tax is a bit much when you can get an actual computer, a MacBook Air, for around $100 more. To me, the iPad is getting a bit expensive at that point for what amounts to a "big iPhone", entertainment/email/web browsing device. A 32 GB Wi-Fi only model at $599 seems to hit a nice sweet spot.
Just my point of view, yours may vary.