I noticed the same thing, Wavelab would rip through the resampling really quick. When using sound forge, resampling at the highest quality setting (and anti-aliasing filter enabled ) it takes a LOT longer.
Because of this I use Soundforge for my resampling. Like the previous poster said, resampling is a process that involves some heavy-duty number crunching. For a given quality of resampling I don't think there are any shortcuts to reduce the time it takes, other than more processing power (=faster computer). Thus I think that wavelab must be using an algorithm with much less resolution, and I'd prefer to get the most out of my recording when doing the 48>44.1 conversion. I usually will open all the files I need to resample and start crunching them when I go to bed, that way they are all done when I wake up. in the morning. Dither down to 16 bit, save the 16/44.1 files, track em' in CDWAV, save the CUE sheets, and extract the individual tracks for the high res and low(er) resolution WAV files...
Peace out-
Ben