I like semi-autos because they are much easier to conceal. If you look at the same overall length, the semi-auto will have a longer barrel (greater velocity and slightly better accuracy). This is simply due to the design of revolvers, which require a cylinder and set the grip further back. Most compact semi-autos are much slimmer than revolvers too. The cylinder is the main issue.
When it comes to trigger pull, I still prefer my semi-autos to any revolver since I carry a Glock 26 or a Kahr MK9. The Glock's Safe-Action is only a 5.5 lb. trigger pull with a very shirt reset and the Kahr is a very smooth DAO striker fired gun.
You guys mention that revolvers are more reliable. I'm sure many members on this board can attest to firing thousands of rounds through their semi-autos without a single hiccup. As long as you take care of your gun, it should take care of you.
Someone mentioned that some semi-autos can be prevented from firing by pushing the slide back slightly. While this is a stretch at best, how likely is that? Double action revolvers can be kept from firing by grabbing the cylinder and preventing it from turning (unless already cocked back into single action).
Regarding ammo capacity, most semi-autos hold more ammo than revolvers of the same size. Reloads are much easier to carry as well due to their slim profiles. In my Glock 26, I can carry reloads of 10 shots each while compact 5 shot revolvers would require 1 speed loader just to match the original capacity. With a While Jerry Miculek can reload his revolver faster than I can reload my semi-auto, most people can reload semi-autos way faster than they can revolvers.
Second strike capability is over-rated unless your gun has a problem with light strikes. A second strike will rarely set off the round unlessthe first strike was a light strike. The reliability of factory loaded center fire ammo is extrememly high and dud rounds are very rare. While the revolver may have the slight edge in speed here, simply racking the gun does not take that much longer. Furthermore, failure to fires are so rare in quality firearms, that there is practically no advantage with the revolver.
Some people mentioned more powerful rounds in the revolver. There is no argueing that assertion, but how many people carry anything geater than a .357 magnum for self defense? If you are using it as a hunting backup or live in bear country, I understand. Besides, according to some threads, most modern handgun bullets have similar stopping power.
When it is all said and done, I'll stick to semi-autos. Thanks!