Here's a much more pithy observation: Lots of times, I drop any pretense towards the photo community features and just use Flickr as a glorified photo hosting service. No shame in that -- it's good as a straight up photo host.
Since the embedded photo links to its Flickr page (as per Flickr community guidelines), it's easy for people to click through from the blog to see my other crappy photos.
For the people on the Flickr side, I usually include a hyperlink in the photo's description ("for a blog entry") that links back to the relevant blog entry.
Doing a Flickr-wide search on the phrase "blog entry" shows lots of folks doing the same thing. However, a distressing number of people just say the photo is for a blog entry, and don't link to the actual entry, which is the worst kind of tease.
(If I'm using a bunch of photos from one set in a particular entry, I may just link to the entry from the set's description page, which is admittedly lazy. Or I might forget entirely. "Do as I say..." and all that.)
Granted, the traffic you drive to your blog from your photos may only be marginal and incremental. Still, you should do it because:
- It's symmetrical.
- It's useful.
- It shows that you care about what you've done and the theoretical people who are seeing it.