I always get nervous when I see a place with more than 30 to 40 taps, first because I simply can't believe they're turning over every beer they have as quickly as they say (I'm going to bet the DFH 60 min gets a new keg every week, while the dopplebock has been sitting there since they opened). Also, I've noticed even in smaller places with inexperienced or uncaring bartenders, that beer lines can get switched around and not cleaned properly between beers. There's a brewpub around me (which will remain nameless) that has a rootbeer on tap right next to the other beers, and low and behold, sometimes the pale ale tastes like it was made with rootbeer.
A place that has 20 taps that rotate regularly seems more appealing to me than a place that has 100, 20 of which are moving and 80 that sit there and crust up in the lines.
Sorry to be a negative Nancy