The Muon g-2 experiment is one of the last places where there is a reasonable hope of finding discrepancies with the Standard Model of Particle Physics. This Science Magazine article describes what this is all about and why it is relevant. Jester of Resonaances tweets that at this year’s Rencontres there is a talk “Most recent results from g-2 experiment”. This might just be an update, not necessarily the announcement of a discovery but who knows.
As far as I understand, even in the exciting case that we finally find something that the SM does not predict, this will not really change the current state of particle physics. Since this is a high-precision experiment, we will only know that something is wrong with the SM but not what or even at what energy scale. But even so, it would be the first crack in the SM and therefore a thing to celebrate.