Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
Debian is currently the fastest growing Linux distribution for web servers, with more than 1.2 million active sites in December. Debian 3.1 was declared stable in July and it appears that both the anticipation of this release becoming stable, and the release itself, have generated new interest in Debian, after some years where it had lagged behind its more active rivals. This growth is particularly noticeable at some of the larger central European hosting locations, including Komplex, Lycos Europe, Proxad and Deutsche Telecom.
Red Hat remains the most popular distribution for web hosting, and is still the best known distribution outside of the Linux developer community itself.
In fact the non-commercial distributions are growing faster than the commercial Linux distributions across the board at present.