Ah gosh, how to answer that without opening a can of worms
No, the Dibb wasn't the same as the Dish. The Dibb was formed from the UK server dying and sadly meant we lost some great people from the site. The Dish was formed by a small handful of folks who became very close friends (I'm obviously choosing my words carefully because you know, I wouldn't want to imply they were a clique or anything...) who I think felt that the posting guidelines of the Dis was too constrictive for them so they started their own forum where they could talk how they wanted. I'm pretty sure it was their intent to create a rival to the UK DIS and pull a lot of people with them but seeing as they only ever talked to each on the forums they didn't get much take up
Short version:
The DIBB. We lost a lot of good people to the DIBB - Bonzo & AlisonB spring to mind, Bevs97 too. I still consider the DIS a poorer place without those guys as they are lovely people.
The DISH. Nyeh, some people left.