By ease of access I should say that recently thanks to Dan of Linux Outlaws I've started using Gwibber which works like pidgin for microblogging and now I can reach Jaiku or Twitter just as easy as sending an instant message to my friends from a single application.
In the past I have tried to use flock to post with since it has a great tool for writing blog posts, but I find it too much application to launch and use for spontaneous use.
Enter Gnome-blog a.k.a. gnome-blog-poster. Easy to use, pretty powerful application and it is lightweight and most important it's easy to get to with a simple shortcut on the top panel of my gnome desktop even on my eeepc.