The web is becoming increasing about where you are, not just what you're doing/saying/reading/writing.
For instance, earlier this week I was standing in a horrendously long queue to be admitted into a recording of the BBC TV show QI, hosted by national treasure and well-known Twitter user Stephen Fry.
It became obvious to me pretty early on that there were many more people in the queue than there were likely to be seats in the studio - but there didn't seem to be any official in charge to ask what our chances of being admitted were. So, I went to Twitter and searched for "QI".
I got a number of results - many of them useless - but some of them were from other people in the queue. Now, wouldn't it have been handy if I could only have seen Tweets from people within - say - 400 yards of me?
Well, if rumoured forthcoming changes coming to Twitter are true then that may soon be possible. At a conference earlier this week, Twitter API guru Alex Payne told attendees that one of the new features that the micro-blogging site might introduce shortly is sharing of your geographic location at the point of your tweeting.
Yuck! I'm not sure I like that.
There's little enough privacy in the way many people are using Twitter right now, without also providing complete strangers with precise details of where you are.
Yes, I can see why marketroids and developers might love to be able to work out where people are at a particular time, in order to advertise to them more precisely or provide location-specific services, but I can also imagine many circumstances when I would want to keep my precise position completely private.
And let's not forget the Twitter celebrities like Ashton Kutcher, Ellen DeGeneres, Oprah Winfrey, Ryan Seacrest have over a million followers. There are bound to be a few bad apples in that bunch who may have a less than healthy interest in the precise coffee bar where their favourite star is currently having a Skinny Caffe Latte.
Just ask Yoko Ono (46,137 followers and counting) about the dangers of obsessed fans.
I'm no celebrity, but I don't want people to know where I am. If nothing else, information like that could be valuable for burglars who want to know when is the best time to raid my house.
So, here's my message to Twitter. Please don't turn on geo-tagging by default. Force people to make a conscious decision that they want their Tweets to reveal where they are at the time they Tweeted.
Otherwise, I think you can expect an almighty backlash.
(By the way, as it was, I didn't get to see QI. It turned out I was about 10 minutes too late joining the queue. Instead I went to see Star Trek. It was pretty good for what it was - but I will always be a Doctor Who fan at heart).