if you're an iPod person there's also the new Classic
but otherwise the Archos 605 WiFi is the latest device until the Cowon A3 or Q5 come out
The aging A2 is not really worth it anymore (arguable)
And from all I've seen the Wolverine is just bulky, overpriced, with a sub-par screen
I guess you can also check out the upcoming 705, it's like the 605 but bigger with no side buttons, and usually the 700s have car attachment accessories