At least a few versions ago it was okay for basic stuff but quite far behind feature-wise to commercial software, which benefit from more integration, more polished UX, and a large bundle of plugins.

Having said that a tool is a tool and in capable hands Audacity is as good a tool as anything.

When I need 10s of tracks (multiple drum mics, bass, guitars, keyboards, vocal mics, effects, etc.), I prefer to use Cakewalk Sonar. I've also heard good things about Reaper which is pretty inexpensive.

I often end up using Audacity when I'm working on only one or very few tracks (e.g., a video voice over). It works quite nicely for basic edits, trimming, normalizing, etc. without as much clutter (tempo, time signatures, measures, etc.) as some of the more music-oriented packages. With the addition of MIDI tracks, it sounds like Audacity is moving more in that direction but we'll see.