While watching television, I noticed a commercial for Vonage. When the commercial was about to end, and it flashed its usual fine print material, I noticed a line that stated "Vonage 911 Dialing service operates differently than traditional 911". Being the curious one, I typed in Vonage 911 in Google and clicked the first result which led me to: http://www.vonage.com/features.php?feature=911

After reading the article, it definitely put me off of ever signing up for Vonage (not that I had intended to in the first place, lol). It seems like a hassle to connect to the emergency service in the beginning. You are required to fill out an address form where your Vonage setup is located (this is understandable) in order for their 911 to know where you are in case of the emergency. This in itself can take several hours after submitting the form (even if it is a one time thing, what if you need 911 during the form submission wait?) If you decide to switch locations, you have to fill out another form with a new address, etc. etc. etc. 

 The most horrific of course, is that in the event of a power outage, or say ISP malfunctioning, etc. your 911 service (besides your regular service) is not reachable at all. Using a landline phone (or cell phone, if you can reach a signal) still gives you the option to dial out in power outages.

 Even if it may sound silly not to go with Vonage over one little thing such as 911, I find this a highly important factor and definitely don't recommend it.