I think it's great for Britney/Bibi -- as a fan, I'm a little disappointed that we won't see such constant production from her, but as people we all probably realize that this is a great choice and a great opportunity for her. She's also said that she'll have a website with constant updates (reading her twitter, I believe it), though, so it's not like she's going to disappear - and everything she does will be with what I think are the best production values in the industry (maybe digitally overprocessed and with some kind of boring guys, but still -- and hopefully those can change).
Honestly: Jesse Jane, Riley Steele, Kayden Kross, and BiBi Jones/Britney Beth. If there are a thousand girls doing porn, 950+ would do unspeakable things to be listed as #5 in that group.
Digital Playground will want to own the copyrights/trademarks associated with it; it's unique enough that it can get different protections; and all the "britney beth" websites were owned by her agent, now all the 'Bibi Jones' websites are owned by her studio. They also don't want to spend money promoting a character that can then leave (personal services contracts - especially in porn - won't be ordered to be enforced.
So, money and legal. I loved the name 'Britney Beth,' but Bibi Jones is growing on me.