About 9 years ago I posted my 9-5 in this thread and was making ~$45k salary for a company doing SEO/web marketing. I continued doing search marketing for companies since then. SEO/SEM marketing in the enterprise space has come a long way and big brands are understanding the importance of search marketing and paying top dollar (4x more than 9 years ago) for search marketers with a track record to lead their search strategy.
If your good at SEO, document your success. Search marketing is a hot position right now in the corporate world. My advice to SEO's entering the enterprise space and applying for jobs, is to show what you can do up front. Get yourself ranked, whether its a Linkedin profile or personal site, for the the job title/position you are applying for (it's usually so long tail no one else is trying to rank for it and piece of cake) . Always a great talking point during the interview.
As some may want to leave their 9-5, I love mine. I'm doing what I love, SEO! Best of luck to everyone trying to make a living with SEO. The demand is there, go get it!