HuskyPup - 3:55 pm on Feb 23, 2010 (gmt 0)
Bottom line: Flush your browser cache before assessing each test case.
Maybe I go a bit OTT...when testing I not only do this on my main office machine I do the same on my back-up PC plus at least 3 laptops all with completely cleared caches!
I was caught out by that problem many years ago creating me all kinds of problems.
Seems to be the best way to find hotlinks : imagesite:domain.tld -site:domain.tld
Under "Find similar images" I can find loads of mine however none are hotlinked now, personally I don't mind my fellow widget trade's people using my quality images so long as they pay for their own bandwidth etc.