The most insightful part of Garrett's article is this:
Given Jeffery Citron’s previous strategy of drag racing (getting in early, spending huge on customer aquistion, branding, etc) is in full effect at Vonage. This strategy in theory (and many times in reality) thwarts competition as it causes competitors to have to continue to spend heavy on customer acquistion (as much as two to three times what Vonage initially had to spend) while simultaniously Vonage will lower their marketing costs, which will increase cash flow, profitability, etc. This should “protect” Vonage because the barriers to entry and cost to compete are too high for most companies. It has worked before for Jeffery Citron and given that I have experienced a recent decrease in visible marketing, the second phase could very well be in play.
Check out the full article.
On a related note, Andy has some interesting comments on a recent NY Times article on Vonage where they interviewed Jeffrey Citron.