Is it going to be hard to catch the top users? Yes of course.
But should we even care? Unless you're into the gaming aspect of it, or you're just really obsessed with big numbers (note that I shouldn't be the one talking :P) it really doesn't make a difference whether someone has 30k or 300k.
Both a 30k and a 300k user know their way around the site very well. Both are trusted. The only difference is that the 300k user has probably been around a lot longer or simply has a lot more time on his/her hands.
In any case, I find that rep is a pretty poor indicator of expertise past the basics.
Personally, I find it pointless to try to reach the top. The repcap makes it almost impossible since it blocks anyone from "jumping" to the top in a short amount of time.
Out of curiosity, I made this query just to see how much it has affected me. And was mildly surprised that I was near the top.
To me, rep doesn't mean anything past, say 30k. If anything, I care more about delta-rep and vote/answer ratios. The last thing I want is a potential employer to see my profile and go,
"Hey, you spend all your time on Stackoverflow. How could you possibly
get anything done?"
At 70k, in no way do I consider myself a "top" user. I'm never going to reach the top, nor do I care.
I use Stackoverflow because I enjoy it.