There seem to be a number of cases of some odd-sounding marks floating around (I've heard of a few from outside of MSO as well).
Which leaves three possibilities:
1) People just didn't do as well as they'd hoped (unfortunately entirely possible).
2) They've made some really harsh calls with marking/the exams have been a bit harder than previous years.
3) They fudged up putting the marks onto PIMS.
Personally, I think it's more likely to be a mixture of 1 and 2,
but 3 has happened before, so if your 'unconfirmed' marks seem really really wrong, it is
possible that they're wrong.
If marks get confirmed, and you're still confused as to why you've gotten the mark you have, I'd advise going in and having a look at your script at the start of next semester (unlikely to change anything from there, but you'd get answers as to why your marks weren't what you were hoping for).
Hope everyone is happy (enough!) with their marks, and good luck for CELS whenever it comes out. Don't get too disappointed (and certainly don't give up!) if your marks weren't what you were hoping for, there's always MAOR102 to compensate!

(And, if it's any consolation, if you're unhappy with your marks, chances are 90% of HSFY is too, so you're not alone. Heck, I was fairly 'blah' about my first semester marks last year).