If you are *probably* not going to upgrade the machine, get the 13" Air with 8 GB built to order ($90 more at the time of purchase).
The Air has the SSD, the Pro doesn't. It's really that simple. Nothing else really matters at this point since for your purposes, the performance is close enough to not really matter, AND either are much better than what you've been using.
The Air is more than capable of editing 720p to 1080p video (link to benchmarks below), and the Air has a higher resolution than the Pro. I don't understand all of these self professed video/photo editors telling you to get a machine with a lower resolution. The Air will allow you to have more real estate and not feel cramped while doing your work on it. Unless of course you get an external screen. Are you getting an external screen?
Here is the bottom line: The Pro has a faster CPU, yes. However, with a conventional HDD it will BE SLOWER than the Air at general OS tasks. If you are not going to bother swapping out the HDD with an SSD, then stick with the Air. Higher res, lighter, faster out of the box performance and most importantly, handles whatever you will throw at it in the next 2-3 years handily.
Don't really worry about low-voltage vs standard voltage tech speak. Those designations are used to separate ultrabook specs (Air) from standard laptop specs (Pro, etc). In general, ultrabook versions of CPU's (like i5, i7, etc) will be slower, but not by THAT much and certainly not by so much that you will be affected in any great way. In other words, yes, the people on here who maintain that the Pro is faster in CPU tasks are right, but it is not SO much faster that it is worth giving up all the benefits of the Air. Think about the whole package, speed, weight, look and feel, resolution, etc. I think that the possible reduced speed in SOME tasks in Photoshop (or whatever) is totally worth the guaranteed better screen, lighter weight and faster overall OS tasks. And I want to be clear on this, this idea that the Air can't run more than one heavy program is complete BS. In fact, with an SSD and the 8 GB of BTO RAM, you could run more programs better than the Pro in its standard config, which is 4 GB without the SSD.
The notion that if the chassis is thin that this automatically means it will get hotter is bunk. If anything, the Air will be cooler than the Pro because the voltage is lower and turboboost is attenuated in the Air compared to the Pro. Also, again, if you are not going to upgrade the machines, then it doesn't matter how cheap/expensive a future SSD upgrade will be. I can tell you this, in 2-3 years (if you do decide to upgrade the drive), getting a 256-512 GB SSD from OWC or from another standard manufacturer will cost about the same. To clarify, OWC is the company that makes the specialized non-standard Air SSD modules. The standard modules are made by companies like Intel, Samsung, etc. And in either case, BOTH (Pro and Air upgrades) are considered hacks by Apple because they don't support non-Apple branded SSD's anyway.
The people you've talked to that say they can't go back are probably people like you who will enjoy the advantages of the Air. The reason they say this is because the performance is great enough for them. At some point, the returns are diminishing because you don't notice them anymore. Certainly the Pro will allow you to render something faster, but only by 10-15% in most cases, so in actuality we're talking seconds.
Take a look here:
http://www.anandtech.com/show/6063/macbook-air-13inch-mid-2012-review/5
This compares iMovie, Adobe Lightroom, Adobe Photoshop and Final Cut Pro X among the various Macbook Pro's and Air's from 2012 to 2011 to 2010. You will see that the current 13" Air (the one you are thinking of getting) beats most of those machines easily. The only machines that consistently beat the 13" Air are the 15" MacBook Pro and the 15" Macbook Pro with Retina Display. All other Macbook's have lower benchmarks. They don't explicitly show the 13" Pro numbers, but it's between the 15" Pro and 13" Air (and this gap is not that large), which means the gap from the Air to the 13" Pro is also not very large, which is why the tradeoff is totally worth it. Here is a quote from the review (btw, this site is highly reputable, as many ITT will attest):
"The Air 13 is fast enough for day-to-day use, and the higher screen resolution and significant edge in terms of portability make it pretty compelling versus the Pros comparatively portly body and disappointingly low-res 1280x800 display. Which isnt to say that the MBP 13 doesnt have its advantages - its significantly more upgradable (the Air has soldered in, non-upgradable memory, as well as a non-standard form factor SSD, while the Pro has a bog-standard SATA port), as well as an LCD with a wider colour gamut. Plus, if you rely on physical media, its the only one with a DVD drive.
To me, and I suspect to many consumers, the form factor and screen resolution are enough to sway me towards the Air. As someone who owned and loved a 13" MacBook Pro for a long time (a base 2011 model with a Vertex 3 MAX IOPS), I just don't see the allure in the current one. The custom SSD form factor seems like an overblown issue, because Apple is now shipping SSDs with controllers good enough that I don't think they need to be replaced, and a number of SSD manufacturers make upgrade kits for the Air anyways. With that said, I absolutely don't like what Apple is doing about non-upgradable memory, because it means that if you're not willing to pay Apple sometimes absurd memory upgrade pricing, you're stuck with a system that'll be RAM starved after a couple of years. If you switch laptops frequently, that's not as big an issue, but otherwise, it's definitely something to consider. But to me, the Air just feels more modern than the Pro, and if you're buying a system in the next month or two, I think the base 13" Air is the better one to get."
That really says it all.
