"It's a delight" is perfectly correct and usable in written English.
You could use it in sentences like, "This morning's coffee was a delight," or, "The smell of baking bread is a delight."
I've written about the power of Scorsese's vision; it's a delight and, I confess, a surprise to see it celebrated on the most public of stages.
Described like that, it may sound like an essay, but it's a delight, Rohmer's cousin to Woody Allen's Manhattan Murder Mystery.
It's a delight, as is Watt's impressive knowledge of old-school cinema candy.
It's a delight to see Posey spouting Walker's dialogue, a kind of passive-aggressive bad-boss-speak.
Making eye contact not only shows sincerity and communicates trust, it's a delight to look into your partner's eyes when you first say "I love you".
"No, it's a delight," says Wood, still regarded as the band's new boy (he joined in 1975).
For traveling, it's a delight — it tucks into almost anything and is no burden on anyone's shoulder.
So it's a delight when clever culinary novelty hits town.
For the 70s fashions alone it's a delight.
"It's a delight that I'm here," he said.
