I think i also have an easier time getting through audiobooks than i do regular books. I made one or two attempts at reading Zelazny's Lord of Light that drizzled out for some reason pretty early before i got a copy of the audiobook and made it through that just fine and ended up thinking it was very interesting.
So it seems a little strange that although i'm interested in the plot and the setting of Miéville's Perdido Street Station, but i keep tuning it out whenever he gets to the descriptive bits. Whenever the language gets too... flowery? (though that seems like a totally inappropriate term for language describing a gritty steampunkish world) it just starts lowing past my brain without making a real impression. It's kind of odd though since i'm usually perfectly happy with digressions and descriptions. Perhaps it's the nature of the lanaguage he's using? In any case i end up being alternately interested during the plot advancey bits and bored during the descriptiony bits. But that's still a good enough motivation to keep on going through the book. What else am i going to do while commuting anyways? Listen to the radio? =P :)
Plus, as soon as i finish this book i can start the 4th book in Bujold's Sharing Knife series, which just came out on audiobook and which i've been very much looking forward to, despite sithjawa's lukewarm review :)