Nexus One Functionality of nexus one bluetooth / multiple email accounts

1/ With the most recent software upgrade available to the Nexus one to have multi-touch & also to resolve some 3G connectivity issues. With this upgrade, can you transfer files, songs & pictures to another phone via blutooth.
2/ With the Gmail account being the default email in the Nexus one. Can I set up Yahoo email account as well? (These are free email accounts.)

3/ Does it work with paid email account?

Have a nice day.
Thank you & looking forward to your reply soon.

Saving contacts in n1

If you have noticed this is the 2nd time I am posting. I am seriously contemplating getting the N1 to replace my 3GS & unfortunately there is no N1 for me to play with.
One of the most annoying thing about iphone is that you cannot save contacts directly into your sim card like any other normal phones. As you all know contacts are saved in the phone memory. Is this the same for N1?

Also Facebook with Yahoo email works fine in the N1? I am now using Yahoo email in my Facebook & do not like to change to gmail.

Thank you once again & looking forward to hearing from you guys out there.

Not sure about post upgrade, but I know that yahoo mail didn't work pre upgrade.