Ajax shortcodes and widgets to allow visitors to sign up to Campaign Monitor (http://www.campaignmonitor.com) lists
Campaign Monitor have an excellent guide here: http://www.campaignmonitor.com/api/getting-started/
Yes, but it's beta - please let me know if it works for you! Just click the CampaignMonitor button in the post/page editor
The widget falls back to a standard web page request, but will still keep users on your site, unlike the normal CampaignMonitor forms.
The most common faults are:
Check out the debugging guide to find out exactly what your problem might be.