My thoughts on the current arc:
Well, right in these two strips (
here and
here), Gary was rather open about his feelings towards Peggy. Yes, I guess one could object and say "man, he didn't tell her he loves her", but I think we can all agree that both we, the readers, and Peggy got the message: Gary
does love Peggy.
Also, I think Gary has grown as a character, and his feelings towards Peggy are deeper than his feelings for Kiley, Sonya, Yuki, Zii, or DiDi. In fact... I have a hunch that, if the next strip shows Peggy going back to the apartment, it's a bit unlikely that she'll find him in any sort of sexual situation with the aforementioned girls, or any other character, for that matter. On another note, I can't hold Peggy's drunken attempt to get some no-strings-attached action against her. I've seen stuff like that before (in the real world), and I've grown past judging people for it. She felt stressed, she felt out of her depth, and she thought this would help her sort her feelings and thoughts out. Nothing wrong with that.
As for the Matt/Yuki pairing: yes, I know Matt is a character we all love to hate, but let's give the Devil his due: for all his failings, including his competitive fixation on Gary, he's helped him understand himself (remember the encounter with Senna?), he helped Yuki deal with the trauma her dad caused her, and both he and Yuki are happy with what they've got together.
As far as Kiley is concerned, while she's a very amiable character, she's been away for a long time, so I think seeing her back in the comic in any capacity would come with many questions as to her development, and I'm not sure there are enough strips left for a catch-up. Also, I don't think it's in Gary's character
right now to just jump from Peggy to her in an instant. Additionally, there are a few irresponsible and immature (probably in fitting with the whole comic's characters) elements about her: remember the "I found my crazy for my thesis" thing?
Anyway, the way I see it, I think the "Gary & Peggy are single & growing" and "Gary & Peggy go heart-to-heart" outcomes are more likely than not.