Debuting in December 2003, Gintama is one of Weekly Jump’s most popular manga. Like anything, it will come to an end. And that end could be soon.
Update August 20 - 5:01am: It’s official. The Gintama manga is coming to a conclusion in the September 15th issue of Weekly Jump.
Numerous major Japanese sites (here, here and here, for example) are publishing a two-page spread from the upcoming Weekly Jump, which states Gintama will end after five more installments. Kotaku has yet to confirm this report, but this could mean that the manga will come to a close in the next few weeks!