I showed the outcome of Boosters' clash with JLI over the manhunter incident but there was one thing that's considered the most important part of Booster Gold#25 Vol. 1. DC basically screwed over all their titles for this event called Millennium, and for Booster another of his supporting cast was lost in a head-aching inducing retcon. The event was made to introduce the New Guardians, a series of adult themed stories that didn't turn out so great (look up information on their villain Snowflame to get what I mean.)
Instead of just using the panel that's considered the most important of the book I wanted to show the whole page. Why? Well Trixie is awesome. Throughout the whole series she seems pretty meek but unless it's admitting she has a crush on Booster she'll always speak her mind. Quirkly to boot. This is a woman than threatened to cancel someone's appointment with Booster unless he apologized to a cat. ...Trust me, it was awesome. Anyway she knows Booster is upset and tells J'onn off for the league being such jerks to Booster. J'onn flashbacks to the real reason why he's fine with letting Booster come back.
This is perhaps the only good, important or long lasting affects of this event. The New Guardians were supposed to be about the members having children to carry their so-called superior genes. While I doubt Booster is actually related to any of them (he doesn't have an active meta gene for one thing) Harbinger says that Booster will be important for the human race to evolve. Now Extreme Justice sorta used this with face palm worthy results that I assume have been retconned and forgotten for the good of man kind. But Jurgens has said it's still important but hasn't been played out yet.
This will likely be something he does involving time travel but here's another side of the coin. Whether Boosters' related to the chosen or not it's canon that his genes are advanced. The bit above came out of the premise of a group of characters with advanced genes passing those genes to their children. We know Booster is supposed to have Rip who is a genius able to understand a science he says is so complex it's nearly impossible to calculate. Yet he's the leading expert in the field that few can even understand and even minds like T.O. Morrow can't fully grasp. Rips' claims to have mastered different fighting styles from the beginning of time to the end. He's memorized events and likely languages.
I know a lot of people say Rip will have to get his smarts from his mom but I think it's generally implied that this will come from his dad. He has to be born to ensure everything turns out okay.