Just poking my head in here and saying 'sup.
I've been an avid Arch user for quite some time and i've been following the Pi project since their first blog post.
I currently administer upwards of 70 different computers for friends, family, and my own. All of which use Arch. I forced everyone to let me install linux or I would no longer fix their computers. and now... I no longer have to fix computers.
Really the only problems I've had since setting up my administration has been issues related to differing hardware between the machines and the such (think ATI, nvidia, xorg and the like).
I'm particularly keen on the Raspberry Pi because such a cheap affordable device would allow me to substantially reduce my administration overhead (lower than it is already) and would perfectly cover what most of the machines are used for. i.e. browsing, youtube, email, and facebook. I am not in any particular rush to get things moving and I won't be buying one from the first batch, but in the end I can see myself getting a dozen of these guys running for fun and actual use such as to replace the 14 media center PC's which currently run XBMC. I most likely will hold off migrating the web browsing computers and such until an accelerated graphics driver arrives. But in discussing the matter with the computer owners all of them are extremely intrigued by the concept and expressed and interest in moving towards this platform if it meant reduced energy use and ease of administration on my end.
When the purchase restriction is lifted is most likely when I'll b placing an order for about a dozen to start and I will be more than willing to help here with the effort. I plan to stick with Arch and pacman since all my current scripts and self-written utilities will drop right in. I see mention of a possibility for building a dedicated repo and I would be willing to help with such effort if it is undertaken and the help is required.