MySQL upgrade question

[ptgptg]

Hi everyone,
I have a website in two languages, and use versions 2.6.4 and 2.6.7 of website baker on it.
Yes i know, these are very old version of website baker! 
My webspace provider emailed me telling me that they are about to upgrade the MySQL service from version 4 to version 5, and that i should let them know if i want to stay with version 4.
Will there be a difference if i let them upgrade to version 5? should i stay with version 4?
My english part of the website uses version 2.6.7 and the Hebrew part uses version 2.6.4.

While i'm at it, i just noticed that version 2.8 of website baker is out already. How critical is it for me to upgrade and will this be a smooth upgrade (including the Hebrew part).

Thanks a lot guys and girls!

[jbs]

I have basically the same question. Our server has several WB websites and we know we have to upgrade to mysql 5, but don't want to have to go through and upgrade all of the websites if we don't need to right away. Will there be a problem upgrading from mySQL 4 to 5 on WB 4.6.7 websites?