Thanks, guys! I'm glad you all liked it. I'm really happy about how the Vichy Viking turned out.
I got a question on the What-If forum and I thought some of you might be interested in my response to it, so I'll repost it below:
Each of my profiles probably takes an average of about 6+ hours, with about half of that time being research. I'll check serial numbers, unit movement dates, unit strengths, construction numbers, etc. It's not just important for me to get the markings right, but to know WHY the markings are a certain way, then try to verify them with actual photos. That's why my somewhat mocking title on the forum is "rivet-counting whiffer". I'm the closest thing the Whiffing world has to a JMN. I'm not that critical of other people's work, but I want mine to be right.
In fact, I think that making a historically accurate Whif profile is actually HARDER than making a 100% historically accurate profile. Given good enough photographs of the subject, all you have to do is copy what you see in the picture. You don't have to know what any of the markings mean, heck, you don't need to even know what kind of plane it is!
When you're Whifing a profile, you have to know WHY every marking existed on the plane. You need to put the red prop stripe in the right place. You need to know that the white line on the tail is an LSO stripe and you need to change the angle for your plane compared to the real-world example you got it from. You need to make up an aircraft type code if it's Finnish, make up a manufacturer code if it's Dutch, find an unused serial number series if it's British, etc. These are all things that people figured out and did for you 70+ years ago if you're doing a REAL profile. If you're doing a Whif, you need to step into the shoes of some underpaid clerk in a cold Finnish Ministry of Defence basement office and figure out what unused two-letter code is most logical for the aircraft in question. This is both the fun and frustrating part of these profiles. It takes sometimes hours of research. For example, I bought about 2 books and joined a Yahoo group on NEI Aviation just so I could make an educated guess as to what codes the ML-KNIL and MLD would use on Vikings. This isn't a problem for real-world profilers!

From a technical standpoint, I use Adobe Photoshop, currently CS5. Most of my profiles are hundreds of layers (553 with the Vichy Viking), but only about a third of them (190 on the Vichy Viking) are actually visible in the profile, many of them being unused "options" (different kinds of bombs/spinners/etc) or merely stepping stones to get to the final result.
Another thing that's different about the way I do profiles is that almost nothing has multiple colors on the same layer. With the exception of unit markings, I basically make every layer a single color. Also, almost every layer is straight up ff0000 RED. What I then do is apply a color overlay layer to change the color of that layer to what I want. In my experience, it's a bit more seamless to quickly change colors that way. Also, if I want to see the exact boundaries of any particular layer, all I have to do is take off the overlay and it pops right out. The other thing that I like about this method is that it allows me to quickly add things like patterns, strokes, gradients, etc. with very little trouble. If you really want to make it its own layer with the right color (sometime very helpful), just throw in another blank layer and merge them.
Cheers,
Logan