Great application - in principle, what it does is duplicated by Secure Notes in Keychain or 1Password (should you own that), but it is perfectly tailored for entering registration details and nothing else. It also feels entirely Mac-like - unlike KeePassX, which is probably its nearest competitor.
The randomised password generator is also worthwhile; speakable passwords, which have combinations of letters reflecting written English but are not English words, are particularly useful (and memorable, as it turns out).
A couple of minor issues are that passwords are at maximum 255 characters long (one of my registered applications has a 536-character password, for some reason) and attachments are not supported - binary "passfiles", to coin a word, are occasionally used in lieu of ASCII passwords. But these are enhancements, not issues!