How many members hold temple recommends?

I'm really not sure on exactly what percentage of LDS members actively attend the temples.

As a guess, I'd venture around 20% of LDS members have temple recommends. If you figure that roughly 50% of the church members are active in the church, and that of the active 50%, many are kids, and some are newly baptized members, and some are "non-temple worthy adults", 20% seems like a reasonable guess.