There will be an additional two Guitar Hero titles on top of Guitar Hero: Metallica released in the first half of 2009. This was revealed during a conference call with Activision CEO Mike Griffith.
Guitar Hero: Metallica is set to be released at the end of Match (US) and later on in May in Europe. A new Guitar Hero for Nintendo DS will be released during the second quarter (April-June), and a Guitar Hero: Greatest Hits compilation with the most popular songs from the first three titles remade for the full band configuration. Sounds like a spectacular idea, although we could also settle for these songs as downloadable content so we can pick and choose which songs to buy ourselves. We assume the release window applies to the US releases as Guitar Hero titles are usually released a little later in Europe.