All of the Genesis 2.0 CSS Changes. xHTML selectors are listed on the left and the new HTML5 selectors are listed on the right.

genesis-2-0.css

/* Structural
--------------------------------------------- */
#wrap                  .site-container
#inner                 .site-inner
#content-sidebar-wrap  .content-sidebar-wrap
#content               .content

/* Header
--------------------------------------------- */
#header                .site-header
#title-area            .title-area
#title                 .site-title
#description           .site-description

/* Navigation
--------------------------------------------- */
#nav                   .nav-primary
#subnav                .nav-secondary
.navigation            .pagination

/* Entry meta
--------------------------------------------- */
.hentry                .entry
.post-info             .entry-header .entry-meta
.post-meta             .entry-footer .entry-meta
.date                  .entry-time
.author                .entry-author
.post-comments         .entry-comments-link
.categories            .entry-categories
.tags                  .entry-tags

/* Author box
--------------------------------------------- */
.author-box strong     .author-box-title
.author-box p          .author-box-content

/* Comments
--------------------------------------------- */
#comments              .entry-comments
.comment-author cite   .comment-author span
.commentmetadata       .comment-meta
.reply                 .comment-reply
#respond               .comment-respond

/* Sidebars
--------------------------------------------- */
#sidebar               .sidebar-primary
#sidebar-alt           .sidebar-secondary

/* Footer
--------------------------------------------- */
#footer-widgets        .footer-widgets
#footer                .site-footer

/* Search Form
--------------------------------------------- */
.searchform            .search-form
.search-input          .search-form input[type="search"]
.s                     .search-form input[type="search"]
.searchsubmit          .search-form input[type="submit"]