+1. It's pretty much just length that makes a password strong, like the cartoon says, it just takes too long to crack. It's another story if you manage to get some malicious software or similar on your pc that gains access to your passwords. Then it's not going to matter if it's 1000 characters long. AVG antivirus is actually pretty good these days, it has improved a lot... if you're looking for something to use.
The other thing is, the word hacking is very overused, 99% of hacking is just keylogging or a virus or something or even people just giving our their passwords for whatever reason and then becoming compromised. If someone has the ability to actually hack something, they're going to be more concerned with the big targets, eg. government/large corporations/banks.
Also, make sure that email actually was from yahoo, sometimes people gain access that way. By claiming you've been "hacked" and then asking you to change your password or something, but then you get redirected to a slightly different web address.
