OpenSolaris is missing a feature that Sun promised to deliver - Janus - officially called the Linux Application Environment. This technology can take Linux commands and translate them to Solaris so Linux programs can run unchanged on computers using x86 microprocessors. Unfortunately, it's still not ready.
Sun had marketed the Janus feature as a helpful way to let users migrate from Linux in favor of Solaris. Originally seen as a migration tool, Sun seems to be looking towards running Linux side-by-side with their own version of Unix - Solaris.
Director of Solaris marketing for Sun Tom Goguen told News.com, "The interest in doing Linux applications on Solaris has been for migration. But when you talk about running certified data center applications, you're going to run that on the full stack of software that's been certified."
Although Sun still expects to offer and support Janus, the software will now be with us next year instead of this year.