For equal cost, why would you select the MacBook Air over the MacBook Pro? [closed]

I can see that the 13" version of MacBook Pro and MacBook Air is same $1199, but the Pro is more feature-loaded than Macbook Air. Why would anyone buy MacBook Air? What's the catch in this?

I was thinking of buying a MacBook for development purposes, and worried if there's any problem in the Pro version, because it comes with more features (like more storage).

Edit:

Thanks for the answer guys, I bought a MacBook Pro a week ago and already loving it.

The primary cons for the MacBook Pro are:

• heavier and more bulky compared to the Air
• noticeably slower HDD versus SSD at the same price point
• only has a 1280x800 screen resolution

Note: but is confirmed to be a better quality display than the one in the Air, with a more accurate color gamut.

Things that sold me on the MacBook Pro over the 13" MacBook Air: the MacBook Pro is more future-proof and upgradeable and offers more value for the money in my opinion.

• Primarily Upgradeable RAM, the Pro Comes with 4 GB and so does the MacBook Air, but the key point is that I can just order it with the 4 GB for the Pro, knowing that I will be able to upgrade to 8 GB or even 16 GB at market rate for RAM whenever I want to. I cannot do that with an Air, you either order the 4 GB and shorten the usable life of your computer or pay upfront to upgrade to at most 8 GB at a premium price (thats shoddy and I would like to avoid that).

• Secondly the MacBook Pro as of Mid-2012 version still has a standard form factor drive bay where you can purchase and install 3rd party 2.5" SATA Laptop Drives of your choice in SSD or standard hard disk drives.

And then the bonus features in order of importance to me, all of which without the need for external dongles and adapters:

• Gigabit Ethernet

• Firewire 800 port

• SuperDrive (optical drive)

• Standard Audio headphone jack that can do both output or input over analog or digital cables

• Hasn't moved to the new MagSafe 2 adapter format

So the flexibility and value of the MacBook Pro sold me on it, its really sad to note that all MacBooks will probably be Airs (like the MacBook Pro Retina) soon enough and this value option will be nothing but a thing of the past, so enjoy it while it lasts.

I've owned both and personally found the pro to be FAR FAR FAR superior to the air.

As stated in the other answers the air has the advantage of being a lot lighter and solid state drive is also reliable and faster. However, the air is essentially a netbook competitor. I found mine to be not up to the task for most of the things I wanted to do. As a designer and web developer I quite often have illustrator, photoshop, dreamweaver and bridge all running at the same time as well as a web browser or two and and FTP program, the macbook air always struggled with even one or two of these applications and the fan would be running virtually constantly if I wanted to do more than surf the web.

With the macbook pro on the other hand, I have Transmit, Illustrator, Photoshop, inDesign, Dreamweaver, Bridge, TextMate, Microsoft Outlook, Telephone, Chrome and Safari all open as I write this post... and the fan hasn't even started.

The MacBook Air runs at a higher resolution (1440 x 900) vs the Pro (1280 x 800).

For development the higher resolution could be nice if you are only using the laptop screen, if you are running connected to an external screen, this doesn't really matter.

Having looked and worked on both (pre 2012 models), the Pro screen seems to be a better quality with better viewing angles and colours - this is subjective as Apple's website describe them as the same.