There are many large, high-traffic sites today that use hover menus. It has become the default navigation scheme to use because it's the only scheme most designers can think of when designing large sites with a lot of content. What many don't know is that there are a lot of usability issues with hover menus.
Hover menus are like link dumping. You're basically dumping links into a container and calling it a day. You can do better than that. Is that what interaction design is about - dumping a set of links into a relavant category and slapping a menu around that? A high school kid could do that. Real, true interaction designers need to go beyond that.
Interaction designers not only need to understand the many problems with hover menus, but they also need to stop putting so much focus on their menus alone. Menus don't engage users because they are just a list of links. Most users prefer to navigate through content navigation links on the page because they're accompanied by descriptive and illustrative text and images that tell users exactly what they'll get before they click. They see what they want, they click it - it's simple and clear.
On a menu all you see is a text label. While this might be enough for a returning user who has been to the site several times before, most users who visit your site for the first time are going to have to think to interpret it. If their interpretation is wrong, you have just wasted their time and now they have to hit the back button and continue searching. But if you had simple, clear content navigation links on your page, most users wouldn't even bother with the menus and would just go straight to that.
A lot of user navigation problems can be solved by eliminating hover menus and choosing a better alternative, and by designing better content navigation links on your page. These are insights that every serious interaction designer needs to know when they're designing at website.