<%  email_user = RepositoriesHelper.users_by_commits(@commits) %>
<ul class="commit_list">
<% @commits.each do |commit| -%>
<% user = email_user[commit.committer.email] %>
<li class="commit_item">
  <div>
  <a href=""><%= link_to h(commit.id_abbrev), 
    project_repository_commit_path(@project, @repository, commit.id) -%></a> 
  by <strong><%= user ? link_to(user.login, user_path(user)) : h(commit.committer.name) -%></strong> <%=h time_ago_in_words(commit.committed_date) -%> ago
  </div>
  <%= gravatar_frame(commit.committer.email, :size => 32) %>
  <div class="commit_message"> <%= simple_format(h(commit.message)) -%></div>
  <div class="clear_left"></div>
</li>
<% end -%>
</ul>

<%  email_user = RepositoriesHelper.users_by_commits(@commits) %>
<ul class="commit_list">
<% @commits.each do |commit| -%>
<% user = email_user[commit.committer.email] %>
<li class="commit_item">
  <div>
  <a href=""><%= link_to h(commit.id_abbrev), 
    project_repository_commit_path(@project, @repository, commit.id) -%></a> 
  by <strong><%= user ? link_to(user.login, user_path(user)) : h(commit.committer.name) -%></strong> <%=h time_ago_in_words(commit.committed_date) -%> ago
  </div>
  <%= gravatar_frame(commit.committer.email, :size => 32) %>
  <div class="commit_message"> <%= link_to simple_format(h(commit.short_message)), project_repository_commit_path(@project, @repository, commit.id) -%></div>
  <div class="clear_left"></div>
</li>
<% end -%>
</ul>

Make commit message linkable, and only show the short message
Make commit message linkable, and only show the short message
