What needs to be done now seeing 90 trial period has been reached?
90 days is simply the minimum length of the beta phase. It is rare to graduate at ninety days. Robert Cartaino (a Stack Exchange employee) has written an answer about this on a MSO question, "Are there any clear and objective criteria when the public beta site will graduate?". I'll quote here it for simplicity:
failed to fullfill that criteria in 90 days, it can be trapped
No, 90 days is NOT a do-or-die date; Not in the least.
90 days is a minimum length. Most sites will take much longer. Longer-running betas are not in some sort of failure mode, nor are they "trapped."
It's blog post time…
Once you're done poking around the numbers, the decision to graduate (or not yet) is about lock in. You're trying to determine if the work of "community building" is done. That's not easily measured by the numbers so I can't point you to "the criteria." It's more about … "Has the site grown into a stable and growing collection of high-quality content with a community that all-but-guarantees continued success for a long time to come?" RPG has; Personal Finance has not.
I would highly recommend reading the linked blog post. It goes into detail about the different Area51 stats and when graduation will become a reality for this beta site. In the meantime, let's focus on keeping a high quality standard, and promoting the site to fellow genealogists.