These are actually quite minor:
These included a buffer overflow in the wordwrap() function,
Which I've never used.
restriction bypasses in the copy() and tempname() functions,
Which don't matter unless you're using filesystem restrictions (safe_mode or base_opendir), and even then, aren't really critical as there are other ways to bypass these.
a cross-site scripting issue in the phpinfo() function,
Which doesn't matter in the least, as you shouldn't have a public phpinfo() page on a production server.
a potential crash in the substr_compare() function
May be annoying, although I haven't used this myself.
and a memory leak in the non-binary-safe html_entity_decode() function.
This only has annoyance factor - although I haven't used this one either
All in all, I'd say it's not too bad, and I'm not rushing to upgrade just yet (although I will before too long)
Mark
