Callcentric just announced several enhancements to their service, including the support for iNum.
You can now obtain a free inum number and call all iNum numbers for free through Callcentric.
To get your free iNum number, go to http://www.callcentric.com/coverage/international_phone_number and select ‘iNum’ in the list of countries.
As of today the iNum network supports presence and IM (Instant Messaging).
This means that, if the feature is supported by your iNum provider, you will be able to see whether an iNum is available or not, and you will be able to send messages to an iNum in addition to simply calling that number.
The first IM client to be fully tested for presence and IM is Google Talk. And this is how it works:
From Google Talk, add a contact in the format email@example.com (where 883510012345678 is the iNum you want to reach). You can then view the presence of this iNum, make free calls and send free messages to the iNum, if supported by your iNum provider.
Most of the iNum providers do not support that feature yet since it has just been released today, however they have now started to implement it. Please check with your provider to see whether the feature is already supported.