I do not really see a bug here. This thread branched off from your initial posting to style issues which is what I am really responding about. 7.03 is just a bug release that fixed the confirmed bugs noted in the release notes. The confirmed bugs are listed right in the release announcement.
The next previous image queries whether or not prev or next images links appear depend on the various queries presented. Depending on how you click in to view a photo will depend initially what query is used. What cookies you have stored for sort etc. Like if a ppuser variable is present we only present results for that user. There is the sort the limit the date variables. There are like 7 or 8 different queries that can be ran to get the next prev images so in any given query or sort you can have or not have next or prev images so its entirely possible to get varied results here. Given that scenerio there is no bug.
If we only issued on query to grab next previous images then your results would be the same each time however this function has never been coded like that.