using ULA for 'hidden' v6 devices?

[streiner at cluebyfour.org (Justin M. Streiner)]

Is anyone using ULA (RFC 4193) address space for v6 infrastructure that 
does not need to be exposed to the outside world?  I understand the 
concept of having fc00::/8 being doled out by the RIRs never went 
anywhere, and using space out of fd00::/8 can be a bit of a crap-shoot 
because of the likelihood of many organizations that do so not following 
the algorithm for picking a /48 that is outlined in the RFC.

There would appear to be reasonable arguments for and against using ULA. 
I'm just curious about what people are doing in practice.

jms