WP Hourly 1.0 is KAPUT! Done! Over with!
It was initially build making use of the standard WordPress Custom Post Type functionality. This was some 3+ years back. Using it for our client wordpress development services we learned that the database grew so big, it became impossible to use it.
Not only was the User Interface (standard WordPress) not that friendly for a project management system, but all the meta data piling up really brought things to a still.
We therefore launched WP Hourly 2.0, which is 100% completely recoded and using a new architecture in the back end.
What if you tracked time with v1.0 already? #
Firstly, before installing v2.0, please DO A BACKUP!
After that, you should be safe to install WP Hourly v2.0. This is because we built in a mechanism that would migrate everything over for you seamlessly. We used it for our self as well and it worked just fine. Still, please do a backup, just to stay on the safe side.