Delays to Windows 2000 could push the release of the commercial version back into 2000, despite Microsoft Corp insisting that it is on track for the end of this year. The delays could tempt large corporate users to wait instead for Microsoft’s 64-bit operating system – code-named Janus – which was demonstrated briefly at the Intel Developers Forum last week.

The Release Candidate 2 of the new OS, which was due on Friday, has been pushed back to September 15, with RC3 now due on October 27. This means that – barring further delays – the final beta, the release to market version, will be available the week of Comdex in mid-November. Windows 2000 would likely then arrive in late January or early February, and the RTM data would enable Microsoft to deal with any nagging Y2K problems.

However, this means that, if Microsoft keeps to schedule, the new 64-bit operating system will be available just five or six months after Windows 2000. It is tempting to say that Microsoft (given its performance with NT5/Win2000) won’t deliver, and the company certainly isn’t giving anything away on Janus yet. However, Microsoft and Intel had an alpha version of Janus up and running on a Merced box for Craig Barrett’s keynote at IDF, and observers have noted that Microsoft has a huge development team working to crack the problems of a 64-bit kernel.

Meanwhile, Sun Microsystems Inc is racing to beat Microsoft with the release of a 64-bit OS that runs on Merced. It demonstrated Solaris up and running on IA-64 simulators at IDF last week.