Linux+ job market
Linux employers (and their HR departments) in general seem to care much less about certifications than their MS counterparts. If you can show them you're comfortable throwing up LAMP servers and writing shell scripts, it speaks much louder than passing a basic multiple choice test. I don't think the Linux+ cert is as useless as CompTIA's Green IT cert, but it definitely isn't as widely sought after as their three primary certs: A+, Net+, and Sec+.