Extra $30 will be ridiculous.
Not really. It's perfect. Remebmer, AT&T doesn't WANT you to use this service.
They're building the 3G network as fast as they can, and with all the iPhones and Blackberries being sold they're just barely staying ahead of demand. And just barely.
Add a bunch of laptops (which will suck more data more quickly since they can multi-task much better than phones) and they'll have real problems.
They don't WANT laptops on the network. So charging $30 a month will help them achieve that goal. So really it's the perfect price.