Edit: If you go here http://developers.facebook.com/tools/explorer/ and add 'likes' to the FQL query, you can see many more via the API.

However, I have two issues:

The site is claiming that the likes are used to populate advertising on Facebook. Surely a better way to prevent that is through http://www.facebook.com/settings?tab=ads&section=social&... rather than removing likes? Perhaps I'm being misled by Facebook, but I have presumed that by toggling the option on the linked page to "no one" I would not have my data used to populate advertising in that way.

A second issue is the access the site is asking for; it is significantly too much. Again, I'm not overly familiar with Facebook so perhaps I'm incorrect here, but surely the site only needs fairly restricted access? Maybe the API doesn't allow such fine-tuning, but being allowed to post on my timeline seems excessive.

No need to go through and unlike things for the purpose of hiding your endorsement of it.

I don't like this. Not for what it claims to do, but because it doesn't clearly say what it does do.

"Facebook Unlike". I get that, good name. When I go to the site, I understand I have to sign in with Facebook. That's fine.

Problems:

1) Why does your app require permission to write to my page? You only need permissions to read all the pages that I have liked, nothing more.

2) It is not clear where these FB pages are coming from. I am presented with a handful of FB pages. Now some of them I have Liked and will continue to do so like Photopic Sky Survey. But I am also presented with things like "omg! from Yahoo" and "omg! Insider", but of which I have never and would never like.

3) The term "Unlike" indicates there should be buttons or toggles called "Unlike". At a minimum, hitting "Like" on something I've already clicked should "unlike" it. However, I'm seeing a mix of pages that I definitely have liked and other ones like "omg!" that I did not like. The "Like" button is available on this. If I hit that, am I liking or unliking that page? Its a visual double negative.

4) Once you hit Like, there's no way toggle the button state again. It just turns to Like and stays there.

Login is dead.

1) You're probably right

2) Me and others I know have used this and recognize all our likes. There are cases where you accidentally or unknowingly like something which may explain the Likes you claim to never have liked. I've had my FB account since 2006. I don't know about you or others but there's bound to be some likes you don't remember if you've been a member long enough.

3) I agree - I was a little misled at first thinking there would be buttons to unlike pages. That said, and correct me if I'm wrong, there actually is no way to unlike a Facebook page apart from visiting the original page or clicking the embedded Like button you originally clicked to Like it a second time. I don't think this is the developer's fault. This is a Facebook issue and the developer seems to be working around the limitations of "Unlikes".

4) This is incorrect. If you hover over the grayed out checkmark you can click again to unlike. By default all of them should be grayed out and checked anyway since you've already liked them. Hovering over the check mark will show an X. You click the X and it's unliked. It is hard to understand and not intuitive on a number of levels but again, this is something out of the developer's control.

I understand your concern that we should be wary of random sites that ask us to log in with Facebook and you're justified in having reservations but in this case a lot of your concerns are easily explained by the Facebook API itself. This looks far more legit than not. The only sketchy part about it was the "Log in with Facebook" request - but once you get past that you see it's legit.