In terms of linearity, Deepholm is much better than Mount Hyjal. At the very least, the zone layout tries to disguise the somewhat linear questing; it feels open, despite still being lead around by your nose through a quest progression.
The story that the player experiences here via the quests are much more focused than in Hyjal. Pretty much everything has a direct relation to the fragments of the stone core which must be repaired to keep things from going even more cataclysmic in Azeroth. Here you get to meet Therazane, who is to say at the very least, an interesting figure. Blizzard's design sense, humorous or otherwise, really shines with her. The region she occupies in Deepholm is certainly blinding with its assortment of colors and their vibrancy, but you don't spend a whole lot of time there as it's mainly a spot for daily quests and the Therazane faction quartermaster (which possesses the rare and epic shoulder enchants... hello, Sons of Hodir #2).
The textures and colors of the zone as a whole are pleasant to be around, which left me wishing I could have spent more than one level here rather than in Hyjal. There's really no choice as to where to go for the intended level 82 zone though; unlike for 80-82, you don't have a choice, unless you want to plow through lower-experience quests by doing Vash'jir at 82 which is not something I'd recommend.
The quests in the zone are the usual mix of serious and humorous, with a sprinkling of very annoying ones. Spawns are as erratic as anywhere else. There is also a giant worm in a tunnel that I quite enjoyed, though it will likely leave players who are not very conscious of their surroundings a bit frustrated. During my brief stay in Deepholm, quite a few players voiced their "love" for the worm in general chat.
Overall, the zone had a great feel art, theme and quest-wise. The story felt like one worth participating in, even though it leads to a very linear progression through the zone. Thus far, what we find in Cataclysm, is that there's a story to be told, and Blizzard will have you miss none of it thanks to the the lead-by-the-nose questing.