[Cthulhu_]

In this case, it generates a new resource; ideal for one-off e-mail addresses. If you do a GET on most websites you get a different result as well, e.g. the news has updated or in the case of HN the comments or news order has changed.

[chrisandchris]

There is a difference between „getting a different result“ and „making the result different“. You mean the first one whale the mentioned site does the latter one. The first one is Ok, the second one not.

A subsequent GET may return different data because another POST/PUT modified the data but a GET should never modify the data itself (e.g. i won‘t be able to safe this comment by GET but by POST).