I for one am very glad to hear that there will be iPad models with 3G and those without. I see the device for my use being something that is mostly used at home where I won't need 3G. However, if you want a 3G version Apple has landed some exceptional pricing from AT&T for the iPad.
AT&T will sell iPad owners 3G coverage starting at $14.99 per month for up to 250MB of data use. An unlimited data plan will set you back $29.99 and both plans give free AT&T hotspot access. You can activate the 3G coverage directly from the iPad meaning you don't even have to go into the store.
The best news is that there is no contract required for the access. I sincerely wish they had offered a day rate or a week rate. I could see wanting access for only a day or so at a discounted rate. Apple also unveiled a cool keyboard accessory for the iPad. The iPad docks on the keyboard and you can type documents and other stuff without resorting to the onscreen keyboard.