I use a firewire audio interface with a decent microphone pre-amp and the ability to sample up to 96KHz in 24-bit.
I get why I'd want to use 24-bit for the added dynamic range, especially when using a lot of DSP plugins. But I'm much less certain about the sampling frequency.
I understand why sampling at 44.1 KHz means frequencies approaching 22.05 KHz begin to suffer from sampling artifacts due to the Nyquist theorem. I can't tell the difference, to be honest. Once my signal leaves the digital domain, my analogue gear probably masks a lot of the details in this region and my hearing is definitely not sensitive to 20KHz anymore.
For the sake of obtaining slightly better fidelity of frequencies near 20KHz, I can switch to 48KHz. In my setup I can playback sound recorded and mixed in 48KHz "natively", but I know any potential listeners will be more likely to listen at 44.1KHz. If I burn to CD, it will definitely have to be resampled to 44.1KHz. My philosophy is then that I'd rather do the resampling than rely on whatever arbitrary resampler the listener has. I've been burned pretty badly by automatic resampling in Windows in the past.
Finally there's 96KHz. More than twice as many samples per second than a regular CD. I can see how this extra fidelity might benefit effects processing, especially if you do a lot of advanced processing. I can also see how you might benefit with extreme pitch or time changes, since there's more material you can throw away, yet still maintain good fidelity. I don't burn 96KHz audio DVDs -- do anybody actually use this today?
So the thing is, I can't really hear the difference when recording in 96KHz, but it takes up twice as much space and causes my DAW to work at least twice as much, meaning I can run much less concurrent DSP plugins at the same time.
I don't think I can blame my equipment much and I don't have any plans to upgrade any of it for the moment. I'm using the Mackie HR824 studio monitors in an acoustically decent location with the Mackie ONYX Satellite audio interface.
Am I missing something? Are my ears shot? Are there other properties of recording in 96KHz that makes it worthwhile?