Andy Karl, Sheridan Smith and Jamie Parker
Andy Karl, Sheridan Smith and Jamie Parker

I feel it has been a brilliant year for British theatre. Being optimistic and enthusiastic, I always feel that way to some extent but looking at the nominations for the WhatsOnStage awards today – the only theatrical prizes based on a vote by the theatre-going public – I can't help feeling a warm glow of remembered happiness at so many great nights out.

Obviously, because these awards are chosen on the basis of mass voting, they represent the popular end of theatre, but just look at the rich variety of things we have enjoyed. The Deep Blue Sea isn't exactly a laugh a minute, yet there it is and there too is Helen McCrory's searing performance as its unhappy heroine. Nor is the classic Spanish tragedy Yerma an obvious choice, but Billie Piper's astonishing, heart-rending embodiment of its tortured heroine in Simon Stone's tough-minded re-imagining of Lorca, has catapulted it into contention. And how brilliant to see Ian Hallard's performance in The Boys in the Band, produced by the small Park Theatre, slugging it out with theatrical heavyweights such as Kenneth Branagh, Ralph Fiennes, and Ian McKellen.

I quietly punched the air that Groundhog Day, a truly distinctive musical, has been recognised

The big story of the year, as is proved by Jamie Parker's nomination in that best actor category, is the dominance of Harry Potter and the Cursed Child – a play which has garnered 11 nominations, including those in all the major categories. At one level this might be seen as inevitable since it has been the theatrical sensation of the year. Yet what's so wonderful about the play is that it actually justified its hype. In every respect, from John Tiffany's shimmering direction, to Christine Jones's fluent settings and Finn Ross and Ash Woodward's video design, it is a marvel. But its story was also rooted in human warmth by the performances, which have also been recognised.

There are some lovely nominations peeping out in every list. I am really happy, for example, to see both the warm-hearted Flowers for Mrs Harris from Sheffield and the ground-breaking The Grinning Man from Bristol making an appearance in the best regional production category. At a time when it is hard for regional theatre to make its mark, it's brilliant to see such innovation and courage being recognised. The appearance of The Flick on the best play list is a similar cause for celebration.

Just look at the rich variety of things we have enjoyed

Equally, I quietly punched the air that Groundhog Day, a truly distinctive musical, has been recognised across so many categories – and I love the fact that Charlie Stemp, who gives a breakthrough performance in Half a Sixpence, finds himself competing with such established names as Andy Karl, Michael C Hall, Michael Xavier and Ramin Karimloo in the Best Actor in a Musical section. And, given that it hasn't even opened to the press yet, the success of Harry Potter and the Cursed Childwith its preview audiences makes me look forward to the premiere.

On a day when Andrew Lloyd Webber's foundation has released a report examining "the hideous whiteness" of British theatre and the danger that poses for the development of both professionals and audiences in future, that show, like many of the nominees, is a beacon of multi-ethnic hope. It points the way forward.

Obviously, I have my favourites in each category. I know exactly how I'd vote. But I don't have to; the choices are up to you. And whatever you choose, it's clear we've all had a very good time in our theatres this year. How lucky we are – and long may that luck last.

Vote in the WhatsOnStage Awards here