Unfortunately, I really don't remember where I saw the suggestion, so I can't credit it. In case anyone doesn't know, Flickr is the dominant photo-sharing site on the Internet, now owned by Yahoo!, and, importantly, allows you to tag your photos - to give them labels - which can then make searching easier. You can also subscribe to a tag as an RSS feed, meaning you can watch all new photos being posted on the site under that tag. A few months ago, I subscribed to the 'hongkong' tag, and I've been watching it ever since, sometimes finding it fascinating, sometimes boring, sometimes frustrating.
It's also interesting that Flickr lets you set a license on your photos - either "all rights reserved" or a variety of Creative Commons "some rights reserved" licenses, which generally allow other people to reuse your photos, but allow you to chose whether they can change them, or must use them as-is, and if they can use them commercially. I'm not sure what my legal position is here - I would like to be able to include at least thumbnails here, which is fine with CC-commercial-use licensed stuff, probably not fine with "all rights reserved" stuff, and borderline with the CC no-commercial-use stuff. So, for now, no pics, just links.
Some themes become clear after watching the feed for a while. There are a few regular posters under the hongkong tag - Charles Lam, James Mok and streetdog come to mind, for different reasons. Charles tends to post nature pictures, particularly of birds and insects, describing them as his friends, streetdog tends to post people-on-the-street scenes, almost all taken at such an angle that women's legs are the focal point of the picture - yes, it's a bit creepy, particularly the ones taken from behind. James does take nature pics, but also random street and other scenes - but he's a prolific and talented photographer.
The more interesting photos are probably those from visitors - and there are a lot of people who pass through Hong Kong. Some of them take and publish great photos - landscapes, street scenes, sunsets behind the skyline and so on - but disappointingly, lots and lots of people come to Hong Kong and take exactly the same photos that everyone else takes. Seeing all the photos aggregated makes some trends and common things clear - for example, there are lots of pictures of the airport which, to be fair, is impressive and photo-worthy, but I suspect that most of the photos are either people arriving and excited, so taking pics, or about to leave and realising that they haven't taken enough photos to show to the folks back home. It may be cynical, but I think it's a fair theory.
There are lots of pictures from the peak - most of them not very interesting, in the end. Pictures taken to the north tend to show lots of tall residential buildings, maybe some commercial buildings, and if the angle and level of pollution are right, some harbour and some Kowloon - that one is from Mr. Mok. Pictures to the south are more interesting, to me, because, frankly, it's a much nicer view from above, and people get some nice sunset shots. There are a few particular scenes which show up, almost identical, time after time - two would include pictures of the incense spirals in the Mo Man Temple and pictures of the Star ferry taken from another ferry - although to give some credit, this one is slightly different because it's face-on rather than side-on. Some things change - some stay the same.
I'm going to write more about this in future, because I think it's an interesting topic, but for now, some random thoughts: There are loads of pictures of food, mainly but not exclusively Chinese food. I've been watching for pictures of people I know, and they've come up a few times, but less than I expected - I think it's more common for tourists to post to Flickr than expats. There are some great photos, which capture a moment, or a mood, or sum up some facet of Hong Kong - but there's also a lot of crap. I skip all photos of Disney-related stuff, on principle. It has happened, slightly more often than I'd expect, that I'd go somewhere and find a photo posted of that place on Flickr within a day or two - even non-tourist places - just coincidence, I know, but sometimes a bit of an odd feeling. Once, I've seen a picture which was obviously taken at almost exactly the same time and from somewhere very close to where I was taking a picture with my phone.