I sent an email to sega asking for any news for Y5 and while I didn’t get any they sent me an amusing haiku, here’s their response: 

Eugene, May 20 08:53 (PDT):

Hello Loyal Fan,

I cannot comment.
Stay tuned to the Sega site.
Good information.

An original haiku by the Sega staff

Sega of America
Customer Support

Maybe we should stay tuned, I’m feeling hopeful!

Hopefully Sega will show us something at E3 this year. With Sony’s press conference it would be a great place to say “We’re not forgetting about the PS3 just yet. Boom Yakuza 5!”

We’ll have to wait and see.