I'll try to answer, although you probably won't get fully satisfied with these answers...
1) It's not a definitive number. I don't have the figures with me now, but it's certainly a lot more than 100. I think it's over 1000 songs and more than 500 albums.
The bubbling under albums/songs are just a bunch that I have included in the database as "top 3000 contenders". Of all the albums and songs that are not in the top 3000 or bubbling under, I'm certain that very few (if any) would break into the top 3000, but many of them would beat some of the bubbling under albums/songs if they were included. That's why the bubbling under albums/songs are not numbered.
2) I don't use a point system where each new entry gives a certain additional score. Of course I create a score variable and rank the albums/songs based on this, but a score of 800 doesn't mean that the album/song has collected twice as many 'points' as an album/song with a score of 400. What I'm saying is that my score variable doesn't make any other sense than for the ordering of the albums/songs. I have never published the score, as it would not give any information, just raise a lot of questions.
Albums:
1. Pet Sounds 991.3
2. Revolver 990.5
3. Nevermind 990.1
4. VU & Nico 988.8
5. Sgt. Pepper 986.8
6. Exile on Main St 985.6
7. Blonde on Blonde 985.5
8. What's Going On 984.7
9. Never Mind the Bollocks 984.2
10. London Calling 981.9
Songs:
1. Like a Rolling Stone 988.7
2. Satisfaction 987.0
3. Good Vibrations 983.0
4. Smells Like Teen Spirit 980.9
5. Respect 974.1
6. Sittin' on the Dock of the Bay 965.2
7. I Heard It Through the Grapevine 964.9
8. Johnny B. Goode 964.7
9. Stairway to Heaven 962.6
10. Louie Louie 958.7
Artists:
1. Beatles 24.22
2. Rolling Stones 26.91
3. Bob Dylan 27.88
4. David Bowie 30.65
5. Led Zeppelin 30.90
6. Bruce Springsteen 31.53
7. Prince 31.58
8. Who 31.78
9. Elvis Presley 31.84
10. Jimi Hendrix 32.11
Thanks for picking this up, Stephan. It does make sense to look at the distance between each position in the top 10. There are no gaps further down the list though.
Why they ascend you mean? Because the lower (as in better) albums and/or songs are placed, the less points they get, and thus the higher they are ranked.
Natural logarithm, which is.. if I remember correctly, the power to which e (2.718...) has to be raised to equal the number you want. But it's been a while since I had statistics.