Aricent have published
an interesting survey about the habits of mobile phone users, which also cast some light on requirements for mobility.
Firstly, 79% of respondents said they would prefer a "single number" for work use, that could map to office or mobile. 60% said that they use their mobile in the office (in preference to landline) due to the convenience of the in-built directory. In VoIP, many services exploit the calling directory as an advantage, including the use of presence on buddies in your directory list. Familiar VoIP and IM tools like
Skype,
Windows Live Messenger and
GoogleTalk all exploit this property, and
Counterpath's new Bria Softphone changes from the desktop phone paradigm to the "buddy list" format to provide the same convenience.
Finally, the survey says that 46% of the respondents are making PC-to-PC phone calls, and 36% are making PC to phone calls. The survey was taken during the 2007 NXTcomm event in Chicago, so you can expect a larger than average "mobile geek" effect in the results.