MacBook Pro or Air? What to buy?

If it were me, I'd probably go with the Pro. They really aren't THAT heavy, especially if you get a backpack or something to carry it with.

Now if your meetings happen to take place at various airports, all over the country and/or world, and every ounce counts, then the Air might be the better choice. But if we're talking about just within a single building, or a relatively fixed location like a single city, then I would seriously doubt the added bulk of the Pro would be that burdensome.

The Air would certainly be able to do what you want, but it generally has a much lower end CPU, the RAM is soldered directly to the MLB so you can't upgrade it, and while technically you can upgrade the SSD in the Air, Apple doesn't really make it easy for you to do so. The Pro takes pretty standard DDR3 SO-DIMMs, the HDD/SSD is a standard 2.5" config, and both can be easily accessed by removing about 10 PH00 screws from the bottom case. PH00 screwdrivers are infinitely easier to find than the special pentalobe Apple uses on the Air's bottom case, and then a Torx T5 bit for getting the SSD out is also a bit uncommon (though not overly difficult to find).

The Air upgraded can handle light web video, but I wouldn't even attempt creating a BluRay or even a DVD quality video though as it will take awhile. Personally I carry around photography gear and a MacBook Unibody 13", so weight is more based on my photo gear, but it's a big cumbersome bag to lug around.
http://www.crumpler.com/us/Camera-Bags/Camera-Laptop-Bags/Sinking-Barge-Deluxe.html?LanguageCode=EN&SKU=SIE001-B00150<div>
You personally can probably make do with something allot less bulky, so I would probably just head to the Pro line.
</div>With the Pro line (i7 Quad core), I'd say you could encode a DVD in a reasonable amount of time, probably like 30 minutes, but it would be still nicer to do something like that back at the hotel or home.

I switched from a 15 inch MacBook Pro to a 13 inch MacBook Air about a year ago. The light weight and small size of the Air really does make a difference. The maximum screen resolution available with the Pro is 1280 x 800, while the Air is available with a native resolution of 1440 x 900. This greater resolution favors the Air for photo and video work. I do light video editing and a fair amount of video editing on the Air and it works fine. The speed of the SSD more than makes up for a slightly slower processor. Of course, my year-old Air is running a Core 2 Duo. Adding an SSD to the Pro would make it feel faster; it would also void the warranty. I have not used an i5 or an i7 Mac, so cannot address that question. Good luck!