Agree totally.
When I was shooting weddings, I would use something like a Leica X1 or m4/3 as a second (or third) camera, but never as the main one. Flash Gordon over at mu-43 uses a Leica and mirrorless cameras, but he works with a partner, I believe, who uses DSLR's.
And he's here too
The short answer is yes, yes, yes.
And if you can get your vision across then I'll hire you to shoot my wedding regardless of the camera you use. I've seen great weddings shot on iPhones and crap ones shot on Nikon D3x's. Anyone who chooses a wedding photographer based on the gear they have rather than the images they capture is making a huge mistake.
However, here's the rub. The camera will affect the way you shoot. Saying that the gear doesn't matter is also rubbish. While great photos can be taken with any camera, the camera does have a huge influence on the style and type of photos. The X100 will lend itself to a different style of shooting than a DSLR. Neither is better but if you choose the one that doesn't suit your shooting style then you're in trouble.
I moved to rangefinders because I was shooting fast primes and manual focus on huge DSLRs. A rangefinder was an obvious choice for me. On my last wedding with a DSLR 62% of my photos were shot with a 50mm 1.2. Why carry 15kg of gear when i can carry 6? My partner likes to shoot candids and he likes to shoot long. A rangefinder is the wrong tool for the job. One of my backups shoots only mirrorless. Awesome images but different to my partner. But they both shoot with the cameras that work the way they see the world.
The camera you choose will influence the images you take. You can work with the gear or against it. One is easier than the other.
The X100 and X10 are going to lend them selves to a more thoughtful methodical approach to shooting. If you try to shoot motor drive sequences or you love the look of long lenses then you're going to fail, big time. If you like to shoot at a slower pace, close in then your going to nail it. You'll focus and then wait for the moment. You'll probably shoot at high ISO on the X100 in natural light at the reception because that's where the sensor excels. These are not cameras where you'll shoot 3000 frames in a day. These are not cameras that will give you loads of telephoto compression or razor thin DOF. You'll be shooting more environmental style portraits. The settings and background will be part of your compositions. You'll probably keep your prints to a medium size as you have enough pixels to get to about 14". You'll be in close, so you'll need to be sure of your settings and react well as if your not confident you'll get noticed too much. You should blend into the background. The X10 should be a very useful little camera. Detail shots (brides LOVE detail shots), small groups at the reception and even the odd short telephoto shot. Try a really tight shot of each bridesmaid from a slightly high shooting angle at the long end of the X10 zoom. Personally I'd have a Fuji flash permanently attached to the X10 and shoot natural light with the X100. You've got two cameras from Fuji so your going to have a nice consistency of colour and tone.
Batteries on the Fujis are only average so you'll need a few spares. You'll NEED an external hotshoe flash. And you'll need plenty of memory.
Just shoot to the cameras strengths and around the weaknesses. If you're the primary then make sure the couple are ready for what you can shoot and aren't expecting heaps of candid telephoto shots.
I fully intend to getting down to 2 M9's and three lenses soon. The way I shoot that should be pretty easy. For someone else it would be hell. The only reason I don't shoot an X100 at weddings is that I don't prefer the 35mm focal length. If you've bonded with your cameras you'll be fine. The X10 and X100 are fine image making tools and more than capable of sensational wedding images, in the right hands.
Gordon