I got my Google Voice invite yesterday, and I'm digging into how the service works.  Imagine being able to receive all your calls, texts and voicemails (from home, cell, work, etc.) at one number, and that's Voice in a nutshell.  All US calls are free, you can receive voicemail by way of email or text, and even record calls and store them online for later listening.  And if you need to call Directory Assistance, GOOG-411 is free too (of course).

PC World published a great article a couple weeks ago that summarizes what Voice is and is not.  But it also laid out why the wireless telecoms in particular (like Verizon Wireless and AT&T) are worried they could turn into mere "dumb pipes" that merely transmit data for cell devices if Voice is able to gather steam and gain subscribers.  If Voice can provide and replace the types of 'value-added' services that are the wireless telecoms' bread and butter right now, it could be painful for their bottom line.

It'll be interesting to watch how this plays out.  In the meantime, I'm reading that porting my number to Google Voice may be available sometime in the fall of 2009 too.  I'll probably check into it again when that becomes available.