There are two recent changes regarding IFR GPS operations and pilot responsibility in the USA:
- Updating a permanently installed GPS database for IFR navigation is considered preventive maintenance and must be performed and logged somewhere, similar to a VOR check, by the appropriate person, plus an operational check. See 14.43 Appendix A (32).
Only under Part 91, if no special tools or assembly is required, can just anybody can do it. Otherwise a technician must do it the update for operation under Part 121, 135, etc. See this article for more details. - Starting Sept. 28, 2009, preflight RAIM checks for non-WAAS GPS receivers are required for many GPS RNAV procedures, and likely also for WAAS receivers in areas of non-WAAS coverage.
Pilots have reported having to print a list of RAIM data as thick as a book with their FSS briefing now.
Makes life more difficult than “kick the tires, light the fires and follow the magenta line.” 
AOPA Online: Preflight RAIM checks for non-WAAS GPS receivers
AOPA Online: RAIM Issue Brief
Wally Roberts: GPS Approach Concepts
Flyer Forums UK: Compulsory for pilots to check for RAIM