It appears Boonex is getting closer to releasing Dolphin 7.0.4. If you take a look at Trac:
You can see at the time of this posting they are down to 4 active tickets remaining and it's at 95% complete. Assuming there are not new tickets added or created anyway.
Boonex also made a blog post at Unity:
About Dolphin 7 caching with a few screenshots. Based on the screen shots there will be an added feature in the Dolphin 7 Administration area under Tools...Host Tools...Cache Engines. Which should help you determine what kind of caching is available or enabled on your server. This will be helpful for a lot of people.
I am kind of curious and looking forward to the addition of the spam control and enhancements Boonex mentioned recently and is said to be included in Dolphin 7.0.4 as well.
Will we see a Boonex Dolphin 7.0.4 Beta before they release the full stable version? Good question. It does seem like this is the route they have been going and leaning towards lately. I don't know how many people really take the time to install a beta version just to check things out. Last time Boonex went the beta route the stable version was release shortly afterward.