We have considered it seriously. But then we noticed that the EF team is promising to compile them automatically (a reversal of their original position on the viability of automated query compilation). "Auto-compilation" is described by
Srikanth Mandadi(
http://msdn.microsoft.com/en-us/magazine/hh394151.aspx) as a feature of the June 11 CTP.
Rather than divert resources to building what EF promises to deliver for free, we're staying focussed elsewhere. If the initiative doesn't bear fruit in reasonable time ... we can reconsider.
We're open to the case for revisiting sooner.
Btw, have you tested the performance of the compiled query relative to the ad hoc? There is some doubt on the part of many that one can actually benefit from this feature in real-life queries. It reminds me of the theoretical benefits of canned SQL query plans ... that didn't often show up in the field.