I am watching with interest a new development in achieving higher resolution images with today's DSLRs. The process involves maxizing image resolution by combining several images and performing super resolution algorithms. The program is PhotoAcute and is fairly new. Ewe Steinmueller is performing real-world testing on the application and has posted a diary at the link below. I hope to evaluate the process in the near future.
PhotoAcute Super Resolution review by Ewe Steinmueller