As long as the 4.5 pound weight of the MBP won't cause too much inconvenience for you, I think going with it instead of the MBA was clearly your best choice. As I have studied the matter, I have concluded that every ultra lightweight, the MBA included, is a series of compromises. In order to achieve its sleek form factor and ultra light weight Apple had to compromise in ways that meant the MBA lacked the battery life, RAM capability, graphics, and sheer horsepower the 13 inch MBP. That just goes to show how much more laptop designers can do when they have 4.5 pounds to work with instead of just 3.
Absolutely. If someone is just as happy with 4.5 lb. as 3 lb., buying an MBA would be stupid. The 13" MBP is so incredibly superior in so many ways right now. The CPU is running full out without throttling at a higher clock speed. The GPU is 80% improvement over the former 13" MBP so probably 100% improvement over the MBA. The RAM capability has a 400% improvement capability. The display is higher quality with better color gamut. The battery easily lasts an extra two hours (although most say nowhere near ten hours). The port selection is better on the 13" MBP with FireWire and two USB ports. It also has a kensington lock slot. In addition, the 13" MBP has the highly useless optical drive that has been outdated for at least three years, but it's there none the less wasting space that could be used for a dedicated graphics chip or even an extra SSD or BluRay. The drive options are so superior on the 13" MBP allowing a full 2.5" drive for incredible options and 4X the SSD drive space option. All around, the 13" MBP is an incredible Mac. At $1199, I would buy the low end model, then upgrade the drive to an Intel 160 GB SSD, and then upgrade the RAM to 8 GB. Then I would be completely happy for a month until the MBA is updated... then I would go right back to the MBA... but for the person happy to carry around 4.5 lb. the MBP is sure joy and incredible value vs. the MBA.
In all honesty, right now people would be crazy to buy an MBA unless they really need ultra-portability, thin, and super lightweight and they couldn't wait for WWDC. I wouldn't buy an MBA right now at all. It is 18 months old. It has been the same price as it was for the same technology 11 months ago.
If I had to buy a notebook right now, I would buy a 13" MBP for $1199 or a 17" MBP for $2299 or a Sony Vaio Z for around $3k for a dream system - depending on my needs. If I had to buy a desktop, I would absolutely be happy yo buy a 27" iMac with C2D refurbished for $1449. If I had to buy a server, I would definitely buy a Mac mini Server for $849 refurbished. If I had to buy a display, I would buy a 24" LED backlit ACD. If I had to buy a router I would buy an AEBS. If I also needed a backup system, I would buy a Time Capsule. If I had to buy an ultraportable device for entertainment or observation, I would buy an iPad. If I had to buy a smartphone, I would buy an HTC Droid Incredible. If I could wait until June for a new smartphone, I would buy an iPhone HD. If I had to buy an MP3 player and wanted to play games too, I would buy an iPod Touch. If I just needed a simple MP3 player, I would buy an iPod Shuffle. If I wanted to buy an entertainment/movie playing system, I would buy an AppleTV or Mac mini.
The point here is there are many Apple products worth buying. Apple is doing a lot of things really right. However, the MBA is the worst value it has been in eleven months. It needs an update so badly, that I wouldn't blame anyone for buying ANY other Apple product rather than the MBA. Even the Mac Pro is older than the MBA, but it's still 100% capable of professional grade computing. The MBA has lost its status as the premier ultraportable that dominated every category/component in the ultraportable market. In addition, the MBA is incapable of doing what the average dual OS user wants to do with it... run Windows 7 in a virtual machine which really needs at least 4 GB of RAM.
If you have to buy right now, DON'T BUY AN MBA! If you get one from work, or get one as a gift, or find one in a local bar with an iPhone 3G cover on it, go ahead and be happy with it. If you have to pay real money for it, the MBA the worst value possible in the last eleven months. Even with a few small updates it would be a good value, but for a Mac that will not be relevant in 12 months let alone three years, there is no reason to pay $1799 plus tax for an MBA. If you can get one for $1349 via the refurbished store it's different if you're happy losing a little bit to upgrade and dump the old one when the new one is released.
If you can wait, you will be greatly rewarded or greatly disappointed if the MBA gets EOL'd. Either way, there is no way anyone should spend $1799 plus tax for a current MBA.