Great move, I ask a question then disappear into the holidays for days... So to finally address your very sensible questions that I should have anticipated!
Originally posted by GerryL Does it show up on actual prints or just the file?
No idea - I haven't printed anything with the line. It's pretty subtle, I doubt it would show up except at very large size, which is one reason I'm not worrying too much about it. But if it got worse...
Originally posted by ivoire And is it in every photo? in the same location? and have you tried another memory card?
Every photo (as far as I know), same location, two different memory cards.
The camera just passed image 4200, which seems a little early to be developing faults, although I suppose it could be the result of the slightly rough handling it suffers on occasion.
Any suggestions, further questions?