I lurked for about 5 years before joining. I recall reading opinions here about Landis on his infamous ride to Morzine in the 2006 TdF. Didn't join until 2011.
Don't remember. Not very long, I think. Definitely less than a year.
In fact if I even lurked it was simply during the period it took me to "work up my courage" to join. Now, I don't think you came across as an intimidating bunch, I'm just weird like that and filling in those things can make me really nervous.
Probably about 3 years, at least.
I had been searching online to learn more about up-and-coming riders when this topic (viewtopic.php?f=6&t=17068&start=40) drew me in. Haven't stopped reading the forum since.
Not until earlier this year I gathered the courage to make a small contribution, but I'm still a lurker mainly.