A new lawsuit challenging the constitutionality of the minimum essential coverage provision has been filed in the United States District Court for the Central District of California. The case is entitled Boyle v. Sebelius, and the docket number is 2:11-cv-07868. The suit was filed in the court's Western Division, based in Los Angeles.
The lawsuit is pro se, and it presents eighteen distinct claims--including claims that 26 USC 5000A violates the Eighth Amendment and the Contracts Clause, issues that do not seem to have been raised in any of the other lawsuits.
The complaint is a whopping 342 pages (!), and thus is presented in parts. You can access part 1 here, part 2 here, and part 3 here.