It's an odd thing, watching a television programme on Twitter. I mean the experience of monitoring Twitter at the same time as you are engrossed in something on TV.

Once, you had to wait until the following morning's reviews to have a sense of the prevailing opinion: now, the verdict is instantaneous. Not only that – and this depends on who you're following, of course – it can feel as if you're in your sitting room surrounded by a bunch of smartarses. It can also be an impediment to making one's mind up about things. You find yourself enjoying something, and then read Giles Coren saying it was cliché-ridden and predictable, or India Knight tweeting that it made her want to vomit. It can't do anything other than skew your own opinion.

I had this experience last week watching BBC's Question Time, a programme that may have been designed for the Twitter generation in the way it invites instant responses. Constant reminders of the show's hashtag confirm this view. I am of a generation that can only concentrate on one thing at a time, so I am lost in awe of those who can have one eye on the TV screen and the other on their Twitter feed, and are still able to come up with something pertinent, critical or clever within the confines of 140 characters. Like it or not, we live in the age of the aperçu.

I found Caitlin Moran's running commentary on Ann Leslie's increasingly baffling contributions to last Thursday's programme much more entertaining and illuminating than anything said by the panel. More important, however, is the feeling that, once you're plugged in to Twitter, you never need to feel alone again. If you're incensed by what a particular panellist had to say, all you need is a quick tweet and you'll find lots of people who think exactly same way, or not, as the case may be.

This idea that you're part of a much wider community, peopled – because we are selective in who we choose to follow – with like-minded souls is undoubtedly one of the most powerful attractions of Twitter.

That portrait of the Royle Family, two generations of couch potatoes sitting together watching the same television programme, comes from another time entirely. Even if we watch the same thing, we won't be doing it in the same room, at the same time, or even on the same piece of equipment. "The group experience has been replaced by the virtual experience," said the chief executive of Virgin Media this week. We may not like what this means for family life – it is pretty tricky to gather around an iPad – but it's hard to argue with this assessment. A younger person might even be more comfortable sharing his or her opinions on Twitter or Facebook than with those in the same room. I am not saying this is healthy, but in an age when we increasingly seek engagement, and a sense of belonging, at least these channels provide an outlet.

And when you're sitting there, shouting at Alastair Campbell, it helps to know that somewhere else, someone is doing exactly the same thing.

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