We use the build in coverage application in TeamCity 6 (about to upgrade to 7.1) If we wish to see the code coverage (or other metrics) of a particular build it is fine as we ca
If you want to compare a set of common metrics (e.g. code coverage) across different projects and over time then SonarQube is probably what you want.
You can integrate it with TeamCity by adding a sonar-project.properties file to each project and calling sonar-runner from a command line build step.