Looked at L2 a few years back. Yes, birds are now ordered and start flying 2016. All operational with 24 birds by 2026. Looks good for precisely your comment on ionispheric distortions, macpacheco.
Wish those other characters would post here instead of the Smith thread
edit-http://www.faa.gov/about/office_org/headquarters_offices/ato/service_units/techops/navservices/gnss/mobileAll/WAASoftheFuture.pdf