Thin clients are a neat trick to pull off, especially on an OS largely designed to be single-user. But since they still require a moderately expensive display, inexpensive keyboard, mouse, and speakers, plus an ancillary box of some kind to convert the back-panel connectors for them into Ethernet linkage and back again the question is whether there's any significant cost-saving over using somewhat fatter clients that include everything save the disk storage.

Mid-range processing power and RAM are dirt-cheap these days, and not having to share them (and a single back-end disk interface too, for that matter) with 9 - 29 other users has real value (in fact, the same value that users perceived a couple of decades ago when their personal computers liberated them from time-sharing). Gigabit Ethernet provides better bandwidth to a back-end storage array than a local disk can offer (even if you're piping data in both directions simultaneously), with minimal added latency (since your caching is still mostly local). And centralizing the back-end storage hardware and management while using a standard-configuration middle-weight client provides all the advantages that using a thin client can, without the drawbacks.

At least that's how I see it, but I'd be happy to be educated if I'm missing something.