I do ALL the OS's on ALL the platforms, my main 'thing' is designing working harware platforms from current and bleeding edge technology according to what the customers need, or think they need, with enough head room so they don't max out their stuff in 6 months to a year.
The main reason I'm playing/learning 03, in addtion to the 'know as much as possible', is that I get a special deal from microsoft, it's called 'map' or microsoft action pack, being a systems builder I get ALL the microsoft fully functional business applications for $299, they are all NFR or Not for resale, all their servers, business applications and alot of good microsoft training and monthly update cd's of service packs and such. I'm also a member of the national association of systems builders and get alot of good stuff from them. I just got a full Intel server that included 2 2.4gb Xenon cpu's, dual processor motherboard with dual gb ethernet, raid, scsi, memory, Intel server case, power supply, win2k advanced server w/10 cal, all for $800.
As for linux, I run, sell and install systens with Mandrake, I like the fact that I can install, configure and have online a running DNS server or servers in under 20 minutes from scratch [depends on how fast you can type and add hosts]. The red hat installer never impressed me, like sco, it's overly complicated which may be good for job security but takes too long get up and running for me, plus mandrake has a full admin book ready to go with each new relsease.
I've never [knock on wood

] had a mandrake install go bad. I have also been doing mandrake for home users lately, don't have to worry about viruses and such plus it keeps their kids downloading games and such and filling up hard drives to a minumum

Open office works fine with MS office files so they are happy.
I cut my teeth on AIX back in 90 at bellcore when IBM's RT's came out later to become RS6000's