Both hotmail and gmail instituted a change to their mail systems without asking anyone first.
Now, instead of getting individual e-mails from people, you get these "conversations" like on twitter or facebook or a newsgroup. They call them "threads".
The problems with this are many:
1. If someone sends you two e-mails, you may "see" only the last one, unless you think to "expand" the previous header tab. SO YOU MISS E-MAILS. Not smart!
2. It lumps together "conversations" from different people for some reason, I guess because you forwarded something. This gets confusing, as you forget who you are talking to, and say "Don't tell Joe I said this, but he's a jerk!" and you hit "send" and realize to your horror that you sent it to Joe! Keeping things separate is a good idea, and we do it for a REASON, gmail!
FORTUNATELY, you can disable this "helpful feature" by clicking on SETTINGS (gmail) or OPTIONS (hotmail) in the upper right hand corner (and "more options" in Hotmail) and then click on the "conversation view" option and click "conversation view OFF". In gmail, you have to scroll down to "save settings".
It is annoying when some dweeby HTML coder decides to "upgrade" a perfectly workable site and make it into something annoying and unworkable. But they do it all the time!
At least this time around, they allow us to disable it. But they should not have just put it on there without asking first!
Web-based e-mail is a very powerful and useful tool. Google is poised to own the cloud with Google docs and other features (more about that later). Don't screw the pooch, Google!