Over on blip.tv there is a video of a guy creating a blog post from his BlackBerry 8700c. I have posted the occasional blog entry here on RIMarkable using my BlackBerry, however, unlike in the video where the blogger is actually posting via the web, I use the email to post functionality built into my blog engine.
Now that BlackBerrys are coming with a bit more horse power and expandable memory, I would like to see blogging from your BlackBerry or BerryBlogging as I like to call it move to the next level. I think that a blog editor that would allow you to incorporate images that you take with your BlackBerry or have stored somewhere in memory would be really cool.