iPhoto '11 from iLife '11 has a new set of e-mail templates for sending photos directly from the application.
However - each time it prompts for your e-mail password and doesn't seem to have a "remember" option.
To fix - open Keychain Access (/Applications/Utilities).
Select login (your login keychain) from the top left Keychains list and Passwords from the lower left (Category) list.