Difference between B2 and WordPress

Really the differences are in the things that are added into Word Press. I have only a few minor mods added to my WP as everything is pretty much in there already. Matt and Mike and the other developers have done a great job and continue to. ??

Indeed. They are improving WP at an amazing pace.

There is a much more that has changed from b2 to WordPress than just additional things added. The back end code that is used to connect to the database was entirely rewritten. The front end code now uses objects instead of arrays to hold the data – it is getting closer to a total re-write than it is to b2 at this point. This is not a knock against b2, I loved it – it is just the natural evolution of the product.

Lets say the difference between NT4 and Win2K.
Evolution is the keyword as Alex said. ??

The main differences seem to me to be the integrated blogroll, ability to password individual entries, and saving posts as drafts. Archiving is also slightly more flexible. Hope that helps.