Second the petguide mobile app.. it is pretty awesome..
BUT I didn't actually find myself hating this new update to the site like most. But I have also only used the petguide app so this is the first time accessing the site from my phone.
I am with everyone who wants "Active Topics" added, though I think that might be covered under "Latest" in the menu. I clicked on that and it seemed to list all the threads in active topics. I'll have to play around with it more, but it doesn't seem that terrible to me. I have an S4 too and it didn't load slowly for me.
Commander Charly Titan (GSD)-15 Jan 2010