To take Figaro – the ultimate operatic assault on class distinctions and social hierarchies – and set it on a giant revolve is a gesture as wilful as it is elegant. Not only are divisions of above and below-stairs dissolved in this steadily circling world, but also those of background and foreground, onstage and offstage. By the time the set’s rotations revealed two young valets with their trousers down, relieving themselves up against a palace wall, some few minutes into the Overture, Fiona Shaw had already won her audience and her case.

First the good news. At 73, is Plácido Domingo anywhere near retiring? Er, no. When the question came up in an interview on Sunday (on video below), he answered : "The reason I don't retire is because I can still sing." And then with a glint in his eye: "I still feel I have to know the the right moment. Not to sing one day more.... nor one day less."

According to the programme essay, Philip Glass describes his latest opera as “serious, but also hilariously funny”. All I can say is, if The Trial is his idea of thigh-slapping hilarity then never, ever let him pick the movie on a night out. Whether the humour’s failure to translate lies with score or production is hard to tell at a premiere, but my money lies with the former.

What’s the collective noun for mezzo-sopranos? A "warble"? A "might"? A "trouser"? Whatever it is, it doesn’t get a lot of usage outside a choral context. Where in opera would you ever find multiple mezzos sharing a stage? Hardly anywhere. Except, that is, in contemporary castings of baroque operas.

Usually, anyone bringing tuberculosis and transgression to the regional centres of Woking, Norwich and Milton Keynes would meet redoubtable opposition. In the case of Glyndebourne’s new touring production of La traviata, that would be a shame, because this is a lean, powerful version that reaches straight for the heart and gives it a good squeeze.

Tim Albery’s production of Monteverdi’s The Coronation of Poppea takes plenty of liberties. There are moments when you scratch your head, quietly sigh, and think about your interval drink, or what you’ll eat when you get home.

Monteverdi’s L’Incoronazione di Poppea is an opera with a one-track mind. The music throbs and pulses with dancing desire, suspensions and elaborate embellishments defer gratification, while recitative is poised constantly on the edge of melodic climax. Desire is everywhere, from the innocent flirtations of a young courtier and his lady, to the hopeless love of Ottone and of course the knowing, mature passions of the Emperor Nerone and his mistress Poppea. Without it, there’s a void at the core of the opera – a void no amount of fine singing or playing can fill.

So easily parcelled up as a master of opera buffa, Rossini is a composer who constantly surprises by the emotional and intellectual range of his best work. William Tell, which opened WNO’s current season three weeks ago, is a major progenitor of Verdi, even arguably Wagner: grand opera devoid of what Wagner himself called effects without causes.

So now it’s Minnie Get Your Gun from the director who brought us the gobsmackingly inventive Young Vic Annie (as in sharpshooter Oakley, not Little Orphan). Richard Jones’s subversive but still very human take on Irving Berlin discombobulated its American support and never made Broadway; but there’s little here that would rock the steadily progressive Met (home of La fanciulla del West’s 1910 premiere, with Enrico Caruso as “Dick Johnson” aka quickly repentant bandit Ramerrez).

2014 is the 250^th anniversary of the death of Jean-Philippe Rameau, France’s baroque giant and maverick. To say that the UK celebrations have been muted is to put in generously, reconfirming a national trend that has long sidelined this repertoire in favour of more familiar Italian and German contemporaries. So it was especially good to see the Wigmore Hall full for an anniversary concert from instrumental ensemble Les Paladins and soprano Sandrine Piau.