Please see this recent blog post: http://www.mastercook.com/blog/a-new-and-friendlier-design-at-mastercook-com/
Please note the last two paragraphs in that post:
Because this is a very substantial update, you may find the website is slower than usual during the launch time period. However, once the update is over, you should experience a much faster website overall, as we’ve included many performance enhancements in this release. Thank you in advance for your patience.
If you have any questions during our launch period, please contact Support at firstname.lastname@example.org.
If you have any problems using MasterCook.com including the MasterCook.com web importer, please report those ASAP. These updates happen on a continual basis as we continue to add new functionality to MasterCook.com. Although we do our best to test the functionality with our separate testing servers, sometimes an issue won’t appear in the testing environment but then appears when it goes live to MasterCook.com. Our developers are on hand to address anything that comes up and is reported, including on weekends.
Your existing MasterCook.com subscription will get the new functionality to MasterCook.com too.