If you focus on good (maybe even new or mutated) game ideas, a handy gameplay and overall nice graphics you can make money even as a "one-man-show".
The sellingrates of casual games are growing (in nearly the same way the total playing time of these games lessen ) - good signes for the casual games market.

Your work (and more important your services) must be professional.
You have to be enterprising and have to follow the changerequest of the publisher/s.
Best way (for me) is to send early but good looking prototypes to publishers and work together on the product.

Multiplatfform and online availabillity is important for the current and more and more for the futur market.

AC3/papervision/java has a fast growing community papervision is under heavey construction and getting more and more interesting for the online 3d gamedesing.