CLEC Z-Tel has announced they are going the VoIP direction.
I feel we are a far ways away from seeing the last entry into the VoIP space and that market segmentation and marketing differentiation is clearly needed. Too many of the companies are all saying the same thing, offering the same features and not providing a clear reason to choose, based on any perceived difference.
Technology, while the platform for differentiation is only as used as the messaging that makes users aware of the benefits and features. So far the offerings from the companies that have loaded in some very useful features (i.e. companies like VoicePulse and Broadvoice) have not taken the opportunity to say how they are different. Instead, they are all selling on how they compare to Vonage. That's a huge mistake. All that happens in Vonage gets the comparison and followers go with the viewed market leader.
Only CallVantage has taken the steps to really say how they are different, basing their value proposition it on the Network and the unsaid, but heard difference in sound quality.
For VoIP's emerging players, it really is becoming the time to "sound off" about what makes each one different.