Just changed the filter on my wife's (new to her) 2006 TL. It only has 104k miles on it but so did the filter from the looks of it! Wow, it was awful. Luckily we only had it a week and never really used the A/C yet. The thought of breathing the air through that. Didn't even need the threads on replacing it. Once I knew where it was its pretty straight forward. I used to have to do it on my old Nissan and it was a much bigger pain in the ass than the TL. Just used OEM filter from dealer and picked up some touch up paint too (Anthracite).

 

Doesn't take long for the filter to get in that condition. Have seen them at 30k miles in that condition, if not worse.