Not enough emaciated, starving, dirty people. Totally ruins suspension of disbelief.
Exactly.
Where are they getting all their new, high-quality clothes from?
From the infinite repository of evening clothes aboard the Battlestar Galactica.

(I so hate you as characters, Baltar and Six.

)
Its sad when
Jeremiah (2002) actually was more consistent with the techology:
http://www.youtube.com/watch?v=DDvU0PbhsNM
Indeed.
Abrams and co. played
Modern Warfare far too often. EMP (or whatever) does not work that way ! The crumbling of architecture does not work that way ! You have several ridiculous plot holes ! Gah...
If they still have guns why have they gone back to muskets?
Yep. I severely doubt most gun nuts and gunsmiths would have the knowledge to repair a musket, since the guns they mostly repair or modify are modern semi-automatics and bolt-actions. And that musket looked like it was looted from a museum.
Besides, the whole trailer makes it look like a B movie attempt at a post-apoc exploitation combo of western and swashbuckler fiction.

What was shown in the trailer reminded me of an unholy union of
LOST and
The Postman (black guy and co. are sooo totally not holnists in prettier suits

), plus the Emberverse premise.
And why do I get the feeling that the gratuituous prevalence of bows and crossbows might be trying to cash in on the archery motifs present in
The Hunger Games ?