Vonage to IPO?

ZDNet and WSJ are reporting that the VoIP firm Vonage is planing an IPO to raise $600m, after having raised $400m with VC cash.

If this is true and works out, Skype will need to make its move soon. Either by its own IPO or by acquisition.
What seems odd to me in all this is how the Telcos have stood around
and watched this players move in on their turf. Of all the
possible suitors mentioned for Skype (usual suspects include Google and
News Corp) I never hear the likes of BT or AT&T making their
play. I don't get it.

(btw, at home we use both Vonage as our land line and Skype and MSN Messenger for PC based videocalls).