• Use their existing cellphone or landline number, or get new numbers.
• Route phone calls to smartphones and other locations. One can set up Ribbit to ring multiple landline and cell numbers, as well as Skype. It can also be set to send SMS alerts with notifications of missed calls and transcribed messages.
• Make and receive calls through Ribbit’s web interface.
• When an incoming call arrives, be presented with what Ribbit calls “Caller ID 2.0,” showing the Facebook, LinkedIn, Twitter and Flickr statuses of the caller.
• Transfer calls.
• Receive recorded and/or transcribed messages. Ribbit Mobile offers a choice of vendors, so one can select computer-generated or human-produced transcriptions.
• Archive and search messages.
• Take notes during conversations and attach them to the record of the call.
• Dictate memos.
• Specify what caller ID will be displayed with outgoing calls.

Ribbit Mobile offers several ways to interact with its service, including an iPhone app, plus web-based and AIR widgets for messages, conferencing, dialing and SMS.

With all of these features, I really wanted to like Ribbit Mobile. Unfortunately, at this point, it has some major shortcomings:

• Slow interface speed. The web interface is Flash-based, and seems to be very slow to load. I counted the load time (on my Mac, using Firefox 3.5) at over 90 seconds!
• Poor contact management. Existing contacts can be imported through Plaxo. Plaxo has its own problems, which I won’t go into here, but Plaxo imports are extremely slow (20 minutes for about 1,400 contacts), and the imported contact file does not include the social network information that’s central to the “Caller ID 2.0″ idea. You can go through each contact in Ribbit and add the social network info, but Ribbit deletes all of your current contacts if you re-import from Plaxo, which means that any social network links you add will disappear next time you import an updated Plaxo file. Also, since Ribbit offers no way to export its contact list, you’ll be forced to maintain two separate address lists if you don’t want to be tied to Ribbit.
• Inconsistent linking to social networks. The connections to Facebook, LinkedIn and Twitter seem to require frequent re-linking.
• Limited community interaction. Surprisingly, one must get approval to even view the forums. Not surprisingly, there aren’t many forum posts, which doesn’t strike me as a good sign.

During the beta period, Ribbit Mobile is free, and U.S. and UK residents can request beta invitations. After the beta period ends, Ribbit anticipates that the service will be sold for $10-$30 per month.

Ribbit Mobile has potential, but right now, its slowness and limited contact management mean that it’s not yet ready for daily use. Ribbit was acquired by telecoms firm BT in 2008, so let’s hope that it gets its act together.

Share your thoughts on Ribbit Mobile in the comments.

Ribbit Mobile has more features than Google Voice, and reminds me a bit of VoxOx, which I wrote about a few days ago. This service looks very promising, but, like VoxOx, it isn’t finished yet. I’ve been unable to test it fully, because it doesn’t yet support Sprint cellphones. I also can’t get my contact list to import, either from a CSV file or through Plaxo (the only options Ribbit Mobile supports). I hope to post a fuller review soon.

Try it out, and let us know how Ribbit Mobile works for you.

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