Album length decreasing.

I think format has a lot to do with it. Late 90s was about the time vinyl died, but it is now being revived. There are limitations to how much music you can stick on a vinyl album, whereas a CD is longer, and much cheaper to produce, so even making a 2 or 3 disc album is not out of the question. 80 Minutes is about as far as a CD will stretch to.

I remember James Hetfield once saying Megadeth albums were a rip off because they were only half the length of Metallica albums. But Reign In Blood clocks in at less than half an hour, and no one has ever claimed to have been ripped off by that. Similarly, old Kiss albums aren't much longer than that either, but they still managed a lot of padding...

I also read in the liner notes of one of the Maiden albums (might have been Live After Death) that trying to put 25 minutes of music on one side of a vinyl album was hard for engineers to cut accurately without losing the clarity or depth or heaviness or something, which was why the average album side was 15-20 minutes.

I figure with the way vinyl has been revived, some bands are shortening their albums to fit that again. I've also been looking at a lot of grindcore recently, and some bands only ever release EPs or splits, possibly because it's cheaper, and also possibly because playing fast means it's hard to write enough music for a whole album.

I usually find albums that are 50 + minutes long tiresome. I find that most artists aren´t able to produce enough quality material to justify putting out longer releases. There are are exceptions like Type O Negative, but those are few and far between. Keep the albums at around 40 minutes and I´m usually happy.

Well the longest album I own was released last year at 2 hours, 22 minutes and 38 seconds...I think it just depends on a number of factors such as genre, whether it's self-released or on a label (I reckon type of label makes a difference too) and of course format. 

Well there's obviously going to be a higher risk of filler on a longer album.

Before the advent of the CD, albums were rarely over 45 minutes long...this was in order to fit everything on one piece of vinyl or one cassette tape. I like this length. Many now-classic albums are barely 35 minutes long.

Thanks God.