A prime example of FUD#1 (exaggerating a weakness) is: ``There's no software for Linux''.
It is enough to point out the fact that Informix, Oracle, and Sybase are all releasing their SQL servers for Linux, that there are three commercial office suites, and that all Linux distributions come with the premier web server software in the world, the Apache server.
Granted, software availability is a weakness in the Linux workstation market. For example, using Linux for serious music work is impossible at this time. There is no Linux equivalent to Cakewalk (a Windows-based product beloved by professional musicians for its power and comprehensiveness). [Note: Jean-Francois Lucas <lucas@etca.alcatel.be> points out that an equivalent to Cakewalk, Jazz, is available at http://www.jazzware.com. Thanks, Jean-Francois]. However, for most office tasks software availability is not a problem.