Big Brother Australia viewers deliver their verdict on the new cast and return to old format - as early favourites emerge: 'Gen Z is not ready'

Big Brother Australia is officially back - and viewers were ablaze discussing  Channel Ten's revamped reboot after its premiere episode on Sunday. 

Fans flooded social media, praising the 'authentic' and 'refreshing' new cast, calling it a return to the show's original roots.

'To give the show credit, I like the fact that viewers are given the platform to watch the cast authentically,' one fan wrote. 

'Unlike every other reality show currently on air that manufactures villains and controversy. This makes me excited.'

Another viewer added: 'Mel was fantastic, the cast lacks a little diversity but seem like a good, NORMAL bunch. The look and feel of the whole show is Big Brother. They delivered on everything they promised.'

While it's only the beginning, several housemates have already captured the audience's attention.

Big Brother Australia is officially back - and viewers are loving Channel Ten's revamped reboot

Big Brother Australia is officially back - and viewers are loving Channel Ten's revamped reboot 

Fans flooded social media on Sunday night praising the 'authentic' and 'refreshing' new cast, calling it a return to the show's original roots

Fans flooded social media on Sunday night praising the 'authentic' and 'refreshing' new cast, calling it a return to the show's original roots

'To give the show credit, I like the fact that viewers are given the platform to watch the cast authentically,' one fan wrote. 'Unlike every other reality show currently on air that manufactures villains and controversy. This makes me excited'

'To give the show credit, I like the fact that viewers are given the platform to watch the cast authentically,' one fan wrote. 'Unlike every other reality show currently on air that manufactures villains and controversy. This makes me excited'

One breakout star appears to be Colin, the cheeky 21-year-old MMA fighter with a mullet and moustache who describes himself as a 'mama's boy.' 

Viewers praised his humour and carefree energy, with one fan joking: 'Loving the bromance with Vinnie and Colin,' while another wrote, 'Colin is actually funny and is in his underwear for some reason.'

Meanwhile, Vinnie, a 21-year-old barber and self-confessed flirt, is quickly emerging as a fan favourite. 'Winner prediction Vinnie. But I'm rooting for Mia,' one tweet read.

Viewers are also rallying behind Jane and Mia, calling them 'the ones to watch,' while 49-year-old publishing boss Michael has already been branded the show's first 'most annoying' housemate.

Many long-time fans say this reboot feels closer to the Big Brother they grew up with.

'I appreciate they didn't try to outdo themselves with a big night one twist,' one person wrote. 'The show feels natural, and the cast interactions are genuinely entertaining.'

Others highlighted the mix of personalities, from school teacher Emily, whose germophobia promises comedy gold, to single mum Coco, who's already been dubbed a 'chaos queen' for her razor-sharp wit.

'Gen Z is not ready for old school #BBAU,' joked one fan, referencing the season's back-to-basics format.

Viewers shared their praise on social media - but not everyone was impressed

Viewers shared their praise on social media - but not everyone was impressed

Not everyone was impressed, however, with a few viewers poking fun at the male contestants' strikingly similar appearances. 

'The way they're basically the same person,' one user quipped alongside side-by-side photos of four moustachioed housemates. 

'What happened with the male side of casting this year?'

Others found certain contestants 'annoying' - such as Colin and Michael - and complained that the show is now too much like the UK version.  

There were also reports of technical hiccups, with viewers in New South Wales complaining about freezing and delays on the live feed via 10Play.

Despite minor teething issues, the overall consensus online is that Big Brother Australia has recaptured the charm and simplicity that made it a national phenomenon two decades ago.

As one fan summed it up: 'Growth is realising you judged Colin too quickly - he's brilliant.'

Big Brother Australia continues on Channel 10 and 10Play.