Need some fresh air? Apple has it. After momentarily taking down its online store, Apple unveiled its new line of MacBook Airs -- featuring Mac OS X Lion, launched in the App Store at the same time. The new Airs look the same from the outside, but it's the inside that matters. Both 11-inch and 13-inch models are powered by the Intel Core i5 processor, with the high-end models for both sizes are upgradable to the Intel Core i7. With these processors, the new MacBook Airs are said to be twice as fast as the ones launched last year. Two notable changes -- the inclusion of Thunderbolt I/O and a backlit keyboard. Excluding Sony's own Light Peak implementation, the new Airs, together with the new Mac Minis, will be the third and fourth to adopt Thunderbolt I/O, after MacBook Pro and iMac. Prices start from $999 for the 11-inch model with 64 GB storage, 1.6GHz processor and 2GB RAM. Adding another $200 will bump the storage to 128 GB and RAM to 4GB. These smaller Airs have batteries that last up to five hours. The 13-inch models, on the other hand, start with more generous storage of 128 GB and  cost $1,299. The 256 GB version, the most expensive of all, will set you back $1,599. They both feature a 1.7 GHz processor, 4GB RAM, SD card slot and seven hours worth of battery juice. The new Airs are available in stores today. Source: Apple