First impression: I love the new logo. I also like the design of the new Thor's costume because it really is just a mildly feminised version of the gentleman Thor's recent clothes. She has a metal breastplate (no laughing at the back there!) and that's about it. Most surprisingly? The areas of bare skin on the lady Thor are the same areas that were bare skin on the male version. No cleavage, no bare legs, no thong, no swimsuit: just the same bare arms and lower face. Hell, this costume might actually be more practical because it does include solid body armour over the chest and neck and a buckler over her offhand. When was the last time you saw a female “version” of a male hero whose costumed offered better physical protection?
Hell of a lot better than this one, certainly...
As to what the new Thor is like as a character... your guess is as good as mine. She appears in the last two pages to pick up the hammer and we get a full-page reveal of that new costume I just enthused about for a whole paragraph. I've tried not to spoiler myself here because I wanted a surprise but on the evidence of the issue I don't know who she is (unless she's Freyja, which is sort of implied at one stage).
This isn't to say the issue didn't interest me. Male Thor in his fallen form is interesting and the mystery of why he suddenly isn't worthy hasn't been addressed yet except to say that Odin and the Warriors Three can't lift the hammer either. There's also a coming power struggle between the All-Mothers and the recently returned Odin as they issue conflicting orders to their subjects.
Hopefully issue two will tell us who this new Thor is, either in the sense of her literal identity or just some mission statement of “I believe this and its why I got this cool hammer”.
I do sort of hope its Freyja, though, especially after how Odin treated her as a subordinate in this issue. Gender swapping heroes like this is ultimately about lending extra weight (read: marketing power) to female characters in a traditionally male space. As much as recent retcons courtesy of Keiron Gillen claim sexuality isn't an issue amongst Asgardians we can't get around the fact that gender is otherwise Odin's treatment of Freyja and Sif's entire character arc make no sense. Given all that I can see the worth in Freyja turning her rejection, which I'll bet the rest of Asgard reinforces now the “true king” has returned, into a singleminded drive to prove her worthiness through the most direct route available: proving it to Odin using the only incontrovertible test divinely mandated by Odin.