Like Janet said in the infamous 1993 interview, 'It's dance music, music which is very similar.'
1982: Janet Jackson | Madonna
1984: Dream Street | Like A Virgin
1986: Control | True Blue
1989: Rhythm Nation 1814 | Like A Prayer
1992 - 1993: janet. | Erotica
1995: Design of A Decade | Something to Remember
1997 - 1998: The Velvet Rope | Ray of Light
2000 - 2001: All For You | Music
2003 - 2004: Damita Jo | American Life
2005 - 2006: 20 Y.O. | Confessions on a Dance Floor
2008: Discipline | Hard Candy
2009: The Best | Celebration
The fact that they both became overtly sexual around the same time in the early 90s (well, overtly for Madonna, just plain sexual for Janet), introspective and spiritual in the late 90s, happy in the early 2000s, controversial in 2003/2004... it says a lot. They even released compilation albums in the same year
Let's face it: Madonna and Janet Jackson fans are blood brothers. You can't claim to be a Janet Jackson-hating Madonna stan and neither can you be a Madonna-despising Janet stan - it's just a bloody oxymoron.
So come here, you silly Madonna hoes
Mariah on the other hand...