I really like 1Password for Mac OSX but not so much for iPhone. The new 1Password 3 has included many functionality, where strong password generation and auto fill in are among my favourites. The 1P button in Safari is very very useful.
When it comes to its interface, I've noticed they have made some progress from the early betas, but for me it still feels too cluttered. This is my take on what 1Password should look like, inspired by the Dictionary widget. The Go&Fill menu is similar, but won't let you copy in your clipboard.