A lot of evidence points to the fact that Arthur Weasley may become the next Minister of Magic (ie. Mr Weasley will replace Cornelius Fudge, whom we have grown to hate). First of all, Arthur is the legendary ... well, legend of King Arthur and the Knights of the Round Table (you can see how that works). And JK Rowling bases alot of the names in Harry Potter on classical mythology or ... flowers. So Arthur Weasley may be the next 'King' in magical England.
Secondly, Ron says to Harry and Hermione, 'We've got about as much chance as winning the Quidditch Cup as dad has of becoming Minister of Magic.' And Gryffindor DOES win the Quidditch Cup, again pointing out that his dad may become the next minister.
Thirdly, who else better to replace Fudge than our beloved red-haired friend, Arthur Weasley?
At the beginning of the fifth book (you guys probably have noticed this), Harry starts to pick a fight (Harry, picking a fight?) with Dudley, and while Harry taunts his cousin, a very important clue in the book pops up: 'I know you did Mark Evans two nights ago ...' Unless I'm very much mistaken, Evans is Lily Potter's maiden name. And JK Rowling NEVER puts things like this inside her books without a reason. So, does Harry have an unknown relative, like a long-lost cousin? As Mark Evans is 10 years old in the fifth book, we may see him in Harry's sixth year at Hogwarts.
Why do we think Harry is the heir of Godric Gryffindor? First of all, Harry's parents lived in Godric's Hollow, before they were killed. See the link?
Secondly, in his second year, Harry pulls the sword of Godric Gryffindor out of the Sorting Hat, and Dumbledore tells him, 'Only a true Gryffindor ...' So did Dumbledore hint that Harry could be a descendant of Gryffindor?
Thirdly, well ... it just seems likely that Harry could be a descendant. We've all just suspected it, right?