We hover on NS. :)
Its a challenge to make sure that you don't spend too much time on the site... afterall we have jobs to do and trolling around NS all day doesn't help get that done. But in the same light, spending no time on the site makes us lose time.
Personally I try to spend about 30 minutes in the morning really reading through and responding to stuff, then check the site for 2-3 minutes every hour.
Its actually pretty tricky to keep a balance of working and browsing... its so damn addictive that sometimes I just have to shut down an NS browser window and work for a day without distractions.