Oh, I think it's obvious that this team is turning it around, it's more that fans didn't expect it so soon and are still doubtful it's for real (as am I), but the fact they're getting closer to turning the corner will increase enthusiasm for the team next season, MM or no MM.
In fact, MM could be a useful smokescreen if they want to snatch Harper at a "bargain" price if he doesn't turn it on the second half of the season. He's still a power hitter with a high OBP, and maybe some tweaks could get him back up a notch - but if you could get him on an Upton deal he should still be a reasonable gamble for a team that could use a solid LH power bat.