Is Metal Gear Solid 4 the last of the Metal Gear series

yes! even the creator said so! don't believe me? search it up!

Search it up my butt! MGS4 is not the last metal gear series. Metal Gear Solid: Rising is coming out. don't believe me? search it up!

No. Since Metal Gear Solid 4: Guns of the Patriots, Metal Gear Solid: Peace Walker was released in April of 2010. Hideo Kojima mentioned in an interview that he personally believed this to be Metal Gear Solid 5, in the sense that the development team for this game was the same size as that of Metal Gear Solid 4. Metal Gear Solid: Rising has since been retitled Metal Gear Rising: Revengeance, and is being developed by Platinum Games for release in February of 2013. As of August 2012, Metal Gear Solid: Ground Zeroes has been announced, which will be the next canonical installment in the Metal Gear saga, and will presumably follow the exploits of Big Boss.