Your Club Nintendo July games are here, and it looks like Nintendo is skimping on their usual 3-4 game selection this month, as the only two on offer are Mario Tennis (150 coins, WiiWare) and Electroplankton Rec-Rec (100 coins, 3DS).
As for recommendations, if you haven't ever played a Mario Tennis title, now is a good time. Mario Tennis 64 is my personal favorite in the series, and still holds up today. As for your other choice, keep in mind that Electroplankton Rec-Rec is not the original classic DS game Electroplankton -- it's merely a budget release of the same IP. It's also only $2 on the DSiWare store, so keep that in mind before you drop coins on it.
Oddly enough this deal has an expiration date of July 15th for Rec-Rec, and July 22nd for Mario Tennis. Whether or not Nintendo will have new games later this month, or just wait until August to unveil the new batch is yet to be seen.
I also always like to remind people that Nintendo is working on a way to port over your WiiWare and Wii VC games. So if you're holding off from buying any, there is hope!