Collectible as in valuable, not really. They don't make many special runs, there are large production numbers of any given model, and few are out of production. They go up with general firearms prices, but they don't appreciate like true collectibles. There are three main "premium" brands of revolvers.
Colt is really your most collectible revolver brand. They are out of production (all of them, Colt no longer produces any revolver), are of good quality, and are often gorgeous. There are also some pretty famous Colts like the Python, Anaconda, Detective's Special, etc. The downside to Colt is parts availability. If you plan to shoot it a lot and break a spring or something, its expensive to find the part and repair it.
Pre-lock Smith and Wessons are somewhat collectible. (During the Clinton years, S&W started putting an integrated key hole into the side of their revolvers as a gun lock). Guns like the Model 29 (Dirty Harry's gun), Model 19 (Combat Magnum), etc. have a following but are still pretty affordable and easy to get parts for and repair as their newer key-holed counterparts are still in production.
Ruger is the workhouse brand. They are stronger than S&W or Colt. If you reload ammunition there are your standard recipes, then "Ruger/Dan Wesson only" loads which are only for use in those two brands as they'll damage lighter guns. Then you get "for Ruger Blackhawk/Redhawk only" which is every higher pressure. I also like the weight and durability of Rugers, plus if you ever have a problem you just call Ruger and they take care of it with no fuss.
Non-premium includes Taurus, Rossi, etc. They are low cost, function fine, but don't have the fit and finish, tolerances, and trigger feel of the premiums.
There are also low volume brands that may be great but for whatever reason never took off. Dan Wesson comes to mind. They are great revolvers and a great system for changing barrel lengths on a gun, but the cylinder release is very odd and difficult to use under stress, to they are relegated to target/range guns and being an also-ran.
I chose Ruger because I like the cylinder latch release. You push in to release like the semi-automatic pistol magazine release. I find this faster and easier to manipulate than the "push forward" release of Smith and Wesson and the "pull back" of the Colts. I also shoot my guns quite a bit, and could wear a Colt out.
The different barrel lengths are sort of like different golf clubs. 2" is great for pocket or ankle carry, making it a great backup gun or deep concealment gun. 3" heavy frame is very easy to carry inside the waistband and regular concealment or open carry. 4" medium frame is great for duty carry or outside the waist band carry. They all operate the same and have similar trigger feels, the same grip angle, etc. It keeps it simple instead of switching back and forth between different systems.
Here's the Ruger family photo:
All three are chambered in .357 Magnum.
The 2" is an LCR (Light Carry Revolver) and is current production.
The 3" is a GP100 Wiley Clapp edition. The WC may be a collectible one day, as it was a TALO exclusive and only 2,000 of each finish were made.
The 4" is a Security Six. The "Six" series is out of production, but there were so many made its unlikely to be a true collectible anytime soon. The "Six" series included the Speed six and the Service Six. The "Security" is the top end with adjustable sights. The Service six had fixed sights. The Speed six also had fixed sights, but was a round butt (instead of the square butt of the other two).
I'd like to add a 5" Redhawk in .44 magnum next, but am having trouble finding one at a price I want to pay. The 5" is somewhat rare.