Microblogging is now the preferred way to update publicly your life or activities status. The technique is now used widely due to a generation trained with SMS and small text messages (just like the Post-it note fifteen years before ;-). If you plant to put your life instant messages into a microblogging services. I would suggest you to use identi.ca and not Twitter (or any other proprietary microblogging solution like Jaiku). There are two good reasons for doing so.
The first is a philosophical reason. Software must be free but with the huge success of network services where the software become a service. The software itself looks less important and people tend to forget about its availability. That's why as a user, developer or service provider, you must take great care while using, developing or running a network service. The Franklin Street Statement on Freedom and Network Services published by autonomo.us started to look at the issue and defines what's classify a free (as in freedom) network service. In the area of microblogging services, Identi.ca is following the The Franklin Street Statement on Freedom and Network Services. The software running this microblogging service is free (released in the GNU Affero General Public License) and called laconica.
The second is a practical reason. identi.ca runs better. As I'm cross-posting between Twitter and Identi.ca, I have a script to post on both at the same time :
adulau@kz:~$perl micropost.pl "I really like #webpy... no constraint and full freedom to code your application." Posting to Twitter... 500 Server closed connection without sending any data back Posting to Identi.ca... 200 OK
Yes. I have such errors very regularly, identi.ca works as expected but Twitter is just dying. As you can see for having working service, it's not a matter of investment. You can have better services just because you have motivated people and design by constraint. Another interesting part is identi.ca supporting XMPP but on the other hand Twitter has troubles with XMPP. On practical and philosophical side, identi.ca is the winner. Of course, you shouldn't look at the trends. Trends are for marketers not users…