Most of the time 24 bit 44.1 or 16bit 44.1
Most people have a bottle neck on preamp quality, etc that high res above this is basically lost (even if the preamp, etc indicate they support high res).
While I appreicate high res files and recording, the vast majority of the time clients can't hear the difference at all on their own playback systems, and by the time it is mixed down to a single stereo file (likley at 16 bit 44.1) it loses those things that made the high res sound different.
I record high res also, but honestly is it usually just a waste of disc space. You will hear far more difference in the way audio is processed by various plugins and techniques than you will strictly based on the bit depth and sample frequency. Focus more on things that matter. How many people do you know that have a playback rig that even supports higher than 44.1 16bit? The only people I know that do are recording engineers also. Most musicians don't even have that. Unless they are a hyubrid musician and recording engineer, it seems pretty rare to see a rig that actually reveals the difference or limitations in the source.