[streety]

It looks like a nicely designed homepage that gets your point across well.

I clicked on the "Switch from Delicious?" button expecting to be able to authenticate with delicious and get going straight away. Instead I got a not terribly well presented list of reasons why I might choose to switch. At the very least there should be a clear call to action at the bottom of that list.

For sign-up is the CAPTCHA really necessary? If I understand your service correctly there is relatively little advantage to be gained by signing up multiple spam accounts and the presence of the CAPTCHA will reduce legitimate sign-ups.

[rinnku]

Good points - thanks for the help.

I used the captcha to avoid having robots sign up but then maybe that is overkill?

[streety]

It's likely premature optimisation. You may have a problem with bots signing up but I suspect at this stage it is not as large a problem as recruiting users.

You might also want to think about relying a little less on javascript. Try turning it off in your browser and see what you get. For me it was completely unusable and rather ugly.