Here, with thanks to reader James, it is possible to answer an question that has no doubt pressed many a mind - what does Jonas Kaufmann look like with straight hair? Mozart fans may wish to turn the sound down.
So who'll be on top at La Scala after Stéphane Lissner leaves for Paris in 2015?
The short answer - probably music director Daniel Barenboim, who finds it tough to play #2 to anybody. But there remains a post to be filled, and La Scala's press officer Carlo Maria Cella has just confirmed that a decision will be made by the mayor of Milan later this month. He says there are three neck-and-neck frontrunners amongst the many candidates.
First up is the Austrian outsider Alexander Pereira. In charge of the Salzburg Festival since last year, he ran Zurich Opera for 21 years before that. Previous form includes running Vienna's Konzerthaus and, famously, flogging Olivetti typewriters. Good at raising money and starting fights, bad at being Italian - and his artistic choices are often questioned.
Next is Cristiano Chiarot. A former journalist, his entire operatic career has been with the Teatro la Fenice in Venice. He rose through the press and marketing ranks to become Superintendent in 2010. A vocal critic of public spending cuts.
Finally, we come to Sergio Escobar. Since 1998 he has been Director of Milan's Piccolo Teatro, where he plays a largely administrative role alongside artistic director Luca Ronconi. Before that he held management roles at opera houses in Rome, Bologna, Genoa - and, helpfully enough, La Scala, where he was marketing director and assistant to the general director between 1979 and 1990. His broad exposure to the opera world is tempered by the fact he's been out of it for 15 years.
Crystal balls to the ready.
The Salzburg Whitsun Festival opens on 17 May with a new Leiser and Caurier production of Norma starring the Festival's artistic director, Cecilia Bartoli. Leiser and Caurier revisit their beloved 1950s in the sombre palette of Italian neorealism.
La Ceci has insisted the musical side reflects Bellini's own era instead of reverting to post-Verdian cliche. Her digging around has resulted in a revised score that reverses habitual cuts. The casting of Norma and Adalgisa has been rethought, and Zurich Opera's period orchestra, La Scintilla, has been drafted in.
Naturally the Decca marketing machine has not missed the opportunity to crank into action. A Norma CD
follows hot on the heels of the performance, but with a slightly different cast. Read more and listen to the album on the Guardian website.
photos: Salzburg Festival
Alongside the Riemann hypothesis and the existence of God, one great question remains unanswered.
How old is Plácido Domingo?
Rumours have long circulated. Has the legendary baritenor, who claims, like Gheorghiu, to have started college at the age of 14, shaved a year or five off his age? His official birth date is 21 January 1941, making him 72.
The equally legendary José van Dam is amongst the doubters. He recently recalled how Plácido Domingo once told him he was proud to be a grandfather already at the age of 36. "At the time I was 31, and today Plácido is a year younger than me."
That seals it. Or does it?
Van Dam was born on 25 August 1940, so he would have been 31 in 1971. Yet Plácido's eldest grandchild, the actress and Playboy model Ivonne Armant wasn't born until 16 January 1974, when Van Dam was not 31 but 33. To complicate matters further, paternity wasn't initially acknowledged. Plácido's first 'official' grandchild arrived at a later date, when Van Dam was even older. No-one would question the veteran bass's honesty. But perhaps the passage of time has clouded his memory. It does seem unlikely that his conversation with Domingo could have taken place at the time he recalls, however old Domingo is.
So the mystery remains unsolved. As ever, it seems nothing short of cutting Plácido in half and counting the rings will provide an answer.
Rolando Villazón gave us The Genius of Verdi on BBC4 on Friday night.
Next week it's Wagner's turn, as Tony Pappano flits around Europe for the self-explanatory Pappano's Essential Ring Cycle at 7.30.
The latest opera to be livestreamed by the Bavarian State Opera is Verdi's Macbeth. Conducted by Massimo Zanetti, it features Zeljko Lucic and Nadja Michael as Lord and Lady M.
Not for aficionados of the puffy short, Martin Kušej's unsettling production features topless bunny girls, dirty underpants and a mass public wee.
The live stream begins at 19:oo (6pm UK time) tomorrow, Saturday 11 May.
"German soprano Anja Harteros has withdrawn from singing the role of Elizabeth of Valois in Don Carlo for the performance on 11 May due to acute tonsillitis.
The role of Elizabeth of Valois will now be sung by Armenian soprano Lianna Haroutounian".
Imagine Wagner's Siegfried rewritten by Berlioz. Ernest Reyer's Sigurd, one of those semi-forgotten operas that is performed roughly as often as it deserves, gets a rare outing at the Grand Théâtre de Genève this autumn.
In recent years relegated to the French provinces, this time round it is blessed with the starriest cast it could hope for. The excellent tenor Andrea Caré
(as recently seen in Covent Garden's Nabucco) takes the title role, with Anna Caterina Antonacci
as Brunehilde and Anne Sophie Duprels as Hilda. Cross fingers they make a recording - there's none currently available, and earlier attempts don't really do the work credit .
Amazingly, the soprano who created the role of Brunehilde back in 1884 lived long enough to record part of it after her stage career had ended. Above, hear Rose Caron in 1904 with Des presents de Gunther.
Below, and rather more stylishly, Régine Crespin tackles Salut, splendeur du jour.
Researchers at King's College London are looking for volunteers to help them develop a mobile app for the Royal Opera House.
Applicants have to record their smartphone usage for a week.
The reward for participating is free access to premium paid-for content on the app when it is launched, a 10 per cent discount at the ROH shop, and a DVD of a ROH performance.
For further details, including how to take part, check out the King's website.
All live reports welcome. Meanwhile.....
"Our DSO to Go app has not only helped our live webcasts reach tremendous success around the globe, but has been an accessible sales channel for many first-time concertgoers without prior ticket or contribution history."