Wednesday evening in Glasgow, Scotland - I started the YouTube client on my e72 to watch the latest edition of The Phones Show. Despite showing a full 3.5G signal, the video kept stopping to buffer after just 3 or 4 seconds of playing. After a few attempts to stick with it, I gave up.
Next evening in Edinburgh, Scotland - I tried again. The phone was showing a full 3.5G signal. This time the video played straight through from the start without interruption.
If you don't know the geography of Scotland, the two cities are about 40 miles (about 70km) apart.
I've noticed that 3G can be a bit funny in Glasgow city centre before, but thought I was imagining things.