MPLS as a protection mechanism

I read the thread on NANOG about MPLS in Metro Networks and the replies
danced around this issue but didn't address it directly. I'd like to know
if anyone is/is considering using MPLS as a Layer 1 or Layer 2 protection
mechanism, whether alone or in combination with other protection mechanisms.
By "protection", I am referring to resiliency similar to SONET wrapping.
Would it allow the sale of different levels of protection for individual
data streams?

If so or if not, please contact me off-list and I'll post the compiled
replies (if any).

Marian Stasney
Managing Partner
Telecom Inquiry Solutions
Ofc: 512-295-4410
Cell: 512-845-1546