As with any new endeavor, you first want to get an idea as to the target market.
For instance, how much, now, do you play these type of casual games?
For an example of one revenue stream look at:
But, again, it depends on who is in your target market. This will be of more interest to 30+ yr olds, most likely.
For the younger market you are looking at IPhone and Android, but neither are really using C++ and games that run on their social networking sites.
If you can make a chess game over Twitter for example, two can play, and others can monitor the game, and that may be of interest, but how would you possibly make any money off of it?
Any of these will require you to learn new platforms and languages, and get into GUI work, unless you stuck to Twitter games.
So, for you the barrier to entry is high due to your lack of experience in this area, if you have someone that has considerable java experience, for example, then you may be able to do something moderately quickly on Android, if that person also knows OpenGL (the 3D graphics for Android).
It is doable, how much work, how profitable, depends on the details of your ideas, and the implementation.
You may be able to get some work by writing some casual games for people to use on a business website, for example, "Dress up your child" at GapKids. This would get you experience in doing casual games, and perhaps be a source of revenue.