Skype tipping point? Yep
Richard asked the question earlier in the week and was widely trackbacked, and here's a couple of more datapoints in answering the question. Verisign thinks there are 900m internet users globally, and Point Topic counts 150m broadband lines (registration required, but free and well worth the effort) at the end of 2004. At c.30m registered users, Skype would appear to have penetrated 20% of its addressable market, and with around 2m concurrent users, more than 1% of the world's broadband population is running Skype at any given time. What's more, if the 155m user figure for MSN Messenger in this Financial Times article is correct, then Skype is ahead of MSN in terms of addressable market penetration, and in a much shorter period of time. I'd call that a tipping point.
UPDATE: In the time it took to visit the restroom and get a cup of coffee, an astute reader has chimed in: "May be worth bearing in mind that Skype's addressable market (& MSN's for that matter) is quite a bit more than the 150m broadband subscribers (probably ADSL + cable). It also includes businesses, govts, schools/universities, cybercafes etc with leased-line or other fast, shared connections." True enough, and while my market definition perhaps overestimates the market penetration, my reader's response clearly highlights the greater potential.