Unless you need the video camera, I would still recommend a refurb'd ipad1.
"AT&T Wireless offers the refurbished, 1st-generation Apple iPad 64GB Wi-Fi + 3G Tablet for $429. With free shipping, that's $66 under our mention from two weeks ago and the lowest total price we've ever seen. (It's also $110 under the lowest total price we could find for a refurb unit today and $130 under the best we could find for a new one.) Sales tax is added where applicable. This 0.5"-thick tablet weighs 1.6 lbs. and features an Apple A4 1GHz processor, 9.7" 1024x768 LCD LED-backlit display, 802.11a/n wireless, Bluetooth 2.1 + EDR, up to 9 hours of battery life, and more. A 90-day AT&T warranty applies.
Note: iPad orders require the purchase of an AT&T DataConnect Personal Data Plan. Plans are active for 30 days and automatically renew every 30 days. (A 30-day plan costs $14.99 and can be cancelled at any time.) This item is not eligble for returns or exchanges."
Wirelessly posted (Mozilla/5.0 (iPod; U; CPU iPhone OS 4_3_4 like Mac OS X; ja-jp) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8K2 Safari/6533.18.5)
for surfing the web, the ipad. the iswifter app does a respectable job with flash content if you need to view something in that way. however, it all depends on your surfing habits. the macbook air is a computer, so what you are really asking is whether you need two computers or something different. i think you know the answer
go to bestbuy, buy an ipad (wifi if using at home/coffee shops/with your mobile hotspot or 3g if you don't have wifi access) and give it a try. don't forget to get some kind of cover to protect it. i think you will enjoy it, but if you don't, you can return it