At this point, there are quite a few listserves and organizations supporting parents who homeschool autistic children. And, while it may be tough to find other local homeschooling families with autistic children, it's relatively easy to find homeschool groups, programs and curricula.
One of the biggest issues faced with homeschooling is the reaction of peers and families: questions such as "how will you teach social skills?" and "won't you go crazy?" can make it hard to keep up confidence and energy. There are also issues related to finding and funding therapies, sports and other extracurricular activities.
The greatest "upside" to homeschooling, though, is its absolute flexibility relative to the individual child. If your child loves trains, for example, you can use Thomas the Tank Engine to teach reading and math skills -- an approach that has a good chance of succeeding. As a child progresses, parents can find social and academic opportunities that meet the child's interests and abilities. The Thomas lover may graduate to model train building (incorporating history, reading, drafting, shop and so forth), join a model train club and over time build social relationships based on mutual interests.
Homeschooling a child with or without autism isn't for every family. For some, though, it's a positive approach to supporting a child's passions and abilities outside of the many challenges posed by a school setting.