true...there are a lot of songs that don't really have any pronounced choruses...some of them are either instrumental or a series of chord changes (little if any vocals)or just nothing at all:

Sisters of the Moon
Straight Back
Honey Hi
Fireflies
The Farmer's Daughter
Never Make Me Cry
That's Enough For Me

I can't think of any others offhand...some are not really choruses but may have a la la la thing going on or a note that's held...or they're just plain and simple vague cause they seem to run right into the verses such as:

Brown Eyes (sha la la sha la la etc...)

Second Hand News (bam bam bam bam etc... although one could argue that "when times go bad, times go rough, won't you lay me down in the tall grass and let me do my stuff" is the chorus but it also kind of blends into the verses)

Gypsy (no real "chorus" although one could argue that "and you see your gypsy...you see your gypsy" is kind of a chorus but, again, it kind of just blends in with the other verses)

The Ledge

any others???