It is getting harder to bridge that gap though AFU.
Since season 2000/1 you have had the following teams in the top 4.
Man Utd 6 times (7 after this season)
Arsenal 6 times (7 after this season)
Liverpool 4 (5 after this season)
Chelsea 4 (5 after this season)
Newcastle 2
Everton 1
Leeds 1
Thats as close to it being a close shop with actually being one AFU.
Of the teams to break the monopoly, Everton, it could be argued did so with Liverpool having one (or both) eye on the CL in 2005. Newcastle have no chance of getting back and Leeds, well, they got there on a good young side coming together at the right time, gambled and it failed badly afterwards.
Chelsea have been top 2 in every season since Romans money kicked in, this will be the 4 season on the bounce they are top 2.
Liverpool can only improve with the American money to spend.
Man Utd, well nowt much else you can say. They have the basis of an excellent, youngish team and despite all the worries over the Glazers, haven't disappeared into a financial pit.
Arsenal are the ones who look weakest to me. Henry hasn't had his usual season, injuries playing up, is his heart really in it. They have a new ground (still getting used to), a excellent young team, a manager who doesn't have to spend millions to get good players but I just get this feeling that they need a couple of battlers in their side as its been proved on many occasions that the nice ball players don't like it up em.
I would be surprised, giving the rough make ups of their squads, if Man U, Chelsea or Liverpool were to take a fall out of the top 4 over the next couple of seasons. Arseanal possibly but even then, thats asking a bit.
Also, who is going to challenge them? Some teams get close, some almost do it but these teams struggle to maintain the consistancy season on season to push on and give it a real challenge. They also don't have the strength of squads to maintain a challenge. Look at Spurs,
UEFA Cup run and now down in 9th?
Unless one of the challengers is taken over by a "Roman" then it will be same top 4 for a few seasons yet. Unless one of them employs Greame Souness as manager.