Stan Carey in Sentence First:
Like has undergone radical developments in modern English. It can function as a hedge (‘I’ll be there in like an hour’), a discourse particle (‘This like serves a pragmatic function’), and a sentence adverb (‘It’s common in Ireland, like’). These and other non-standard usages are frequently criticised, but they’re probably older than critics think.
More recent is the so-called quotative like (‘I’m like, Whoa!’), also often disparaged. This became widely established impressively fast and is leading to some remarkable usages in younger generations: children saying things like ‘What’s Ernie like?’ to mean ‘What’s Ernie saying?’
So some uses of like are emerging right now, spreading through younger speech communities. In episode 278 of Australia’s Talk the Talk podcast, guest Alexandra D’Arcy – a linguistics professor who literally wrote the book on like – says that while she might say ‘at like the same time’, her son can say ‘at the like same time’, which is not in her grammar at all. It’s a subtle but striking difference.
It gets better. The latest novel use to which like is being put is as an infix. Infixes are a pretty small set in English, so a new one is a genuine surprise, linguistically. In some ways it is unlikeprecedented.
More here.