Help me with iTunes (I hate iTunes)

Factual Questions
1

OK, here’s the dealio,
before I upgraded to the most recent version of software on my my iPhone, and on my iTunes, I used to have music from my home computer on my iPhone and would regularly sync with my work computer for podcasts and keeping my calendars and contacts in sync.

Now when I do this, it wipes out all of my music from my home computer.

What software upgrade changed all that?
Is there a work around?
and what exactly is “manually manage music and videos?”, and is my problem related to this?

2

Warning the new I-Tunes 9 update is a complete mess, it is playing havoc with podcasts, playlists, I-Phone applications, check out the Apple message boards for help.

3

There was a patch that was sent last night.

4

There’s your problem. ALWAYS set it to manually manage music and videos at home (and make sure the sync is set off for music at work).