I suspect users mentioning this might actually confuse the refresh rate with the delay.
I just posted a topic about the delay:
http://getmusicbee.com/forum/index.php?topic=18095.0 and I think the delay (it's about 250msec.) is much, much worse than a somewhat low refresh rate...
I'm still using 3.0.5927 which has a refresh rate of 15fps and it looks quite snappy in itself BUT there's this delay of about 250msec which causes music with a strong, clear beat, sometimes to show the peaks on the offbeat instead of on the downbeat. So in those cases it's very clear there's something wrong. When there's not a clear beat it may *seem* the visualizer has a slow refresh rate whereas in fact it is due to this delay.
Here's a short video of the "old" visualizer (15fps). It's quite snappy, isn't it? It's without sound but in this particular example the beats are heard exactly between the visual peaks:
www.phenotype.nl/test/test.wmv