- Flash/Flex
- HTML5
- Java
- Unity
- Silverlight
- etc..
The majority of casual games right now are being developed in Flash. If you look at sites like Games.com, Mochi, Mindjolt, and so on...you'll see that 90% (or more) of the content is Flash. Does this mean that Flash is better than the others? Nope. It just means that it's the most common use-case for developing casual games right now.
The question really is how long that's going to be. HTML5 is hot on Flash's heels, and it's really shaping up to be a powerful ally to casual game developers. I just don't think it's ready to usurp Flash's position just yet. The progress is substantial, though, so give it a year or two and it'll be a formidable contender. Adobe knows this too. They have been working on Flash->HTML5 conversion systems, and I wouldn't be surprised if they created a Flash-like IDE for the HTML5 (focusing primarily on the canvas support). As John Nack put it in his article regarding the conversion tool, "Adobe lives or dies by its ability to help customers solve real problems." This does seem the case and I would argue that Adobe's doing a pretty decent job of it. If they did create a full HTML5-IDE (ala Flash), I'd buy it.
Java is a great language for developing games. It's been around forever and has had a lot of push. I'm not a Java game developer, but I've tinkered lightly in the past and I had to do a few projects in college (non-game) using the language. The power afforded by the Java gives the developer a lot of options. The issue I see is that when Oracle took over the company they seemed to have put games off to the side. This doesn't mean that Java no longer offers gaming as a possibility. Far from it. It just means that the company-backing to grow that area of the language is no longer in the forefront...unless something has changed that I'm unaware of.
Unity is a nifty language with a robust graphics engine. It's powerful, 3D, supports builds on various platforms and distribution channels, etc. I've dabbled only lightly in it and I can say it is a very nifty world. Issue: the documentation is less than awesome. There are a lot of things that you just have to figure out. Now, if you're the tinkering type, this may be cool to you; if you're part of a team that is taking Unity and extending it to fit your particular game, then it's a very smart path to go. But if you're a hobbyist or a developer working on time-constrained projects, the learning curve may just be too great until they get their docs in order.
Silverlight is interesting, but I wonder how far it's going to go. With Microsoft behind it, one would imagine it has decent longevity. I wonder why they'd bother pushing money in its direction when HTML5 seems to be heading swiftly toward front-runner position. Personally, I've not developed in Silverlight, so I can't talk to its particular strengths. Still, as time permits, I will create a least a little something so I can see how it all comes together. I just don't see it as an area to spend too much of my time since Flash already has the lead and since I'm guess that HTML5 will soon take the #1 spot.
There are others out there that are available to learn as well, but I think the ones listed are the primary contenders at the moment. Of course I may have completely spaced on one of the other big players. If so, smack me. I'm not proud. :)
The bottom line is that any of the above languages (and more) have their advantages and disadvantages, but if you're looking to pick one or two to learn at this point, I feel that picking the more relevant one makes the most sense. This isn't a case of me saying (or thinking) that Flash/ActionScript is the best and everything else is crap. I don't believe that at all. Actually, there are parts of AS3 that drive me nuts. The point is that I see little value in spending my time deeply learning Unity and Silverlight for web-game development at this time, unless, again, there is a particular need (or job-opening) that requires that expertise.
Playing devil's advocate: There are a load of Flash and Java devs out there already. Companies that are invested in Silverlight, WildTangent, ActiveX, Unity, Torque, etc. are on the lookout for developers that know those technologies.
It's a catch-22. You either focus your time on being a know-it-all about one or two technologies, or you play the jack-of-all-trades card and just be decent in various technologies. I've always gone the second route. The way I see it is that I'm a developer regardless of the language I use. If I am tasked with developing an application in Java, I'll focus my efforts on learning it for that purpose. Same with Silverlight, etc. So I purposefully do not try to be an expert at any single language. To do so, for me, is limiting. ...but that's really a different discussion.
