In an odd turn of events, Nintendo is changing the registered coin values for a ton of games. They're not going to be making the transition on a system by system case either: they're changing the individual values of each title.
What this basically means is that depending on your game, you could either earn more coins waiting for the July 1st change, or more coins registering it right now, before the deadline. Make your plans accordingly, people!
At a glance, it looks like there's an even amount of increases and decreases, but sadly, it looks like most eShop titles are going down to 5 coins each (which are a bulk of my coins these days). If you're curious as to what exactly has changed, take a gander at the three lists in the gallery below, or head straight to Club Nintendo's page to see what's up.
Some Club Nintendo Coin Values Will Change on 1st July [Nintendo Life via Club Nintendo]