The difference between Arsenal this season and previous years is that there aren't any genuinely world class players in their squad any more. There's a few with the potential to be - Cazorla, Wheelchair, Oxlade-Chamberlain etc, but I don't think any of them are at the top level yet. Much of their squad is full of players who are outstanding on their day and absolute dogbrick when confidence is low, see Walcott, Gervinho, Giroud, Podolski, Ramsey, Arshavin etc.
The point is, the likes of Henry, Fabregas and Van Persie not only had the fighting spirit to put in big performances even when the team had been playing badly, but the fact that they could produce moments of brilliance to win matches meant they could pick up points even when the team in general was playing badly, which in turn would restore confidence to the squad with an important win. I'm looking at their current squad and wondering who has it in them to inspire them to come back from being off the pace for a Champions League spot the way Henry did in the 05/06 season, the way Fabregas did in the 08/09 season and the way Van Persie did last season.
What will probably work out well for them though, is that they have a relatively easy run of games coming up. Yeah yeah, there's no easy games in this league, but these are easier than most:
West Brom (H) - WBA have done well this year, but their form has dipped and you'd expect Arsenal to beat them at home
Reading (A) - Arsenal scored 7 last time they played at the Madejski, Reading's defence is absolute brick and again, you'd expect Arsenal to win
Wigan (A) - Martinez is a top manager and good in the big games, but still, Arsenal will be favourites again
West Ham (H) - Arsenal have already beaten them at Upton Park this season, at home you'd think Arsenal will win again
Saudi Sportswashing Machine (H) - Saudi Sportswashing Machine are having a poor season and have a lot of players out injured. At home you'd expect Arsenal to win
Southampton (A) - Southampton have got some good attacking players but they're suspect at the back, a very winnable game for Arsenal once again.
If they're way off the pace after that run of fixtures then I think it might be time to start getting excited, but after a run like that they should go into the January transfer window either in the top 4 or at least very close to it.