I use to think they were cool with each other, because they did a lot of bits together, but it seems like Madonna doesn't like Gaga. Just recently, someone publicly asked her, "What do you think about Lady Gaga?" And she replied, "Lady Who?". I guess that sums up what Madonna thinks of Gaga.
And today, Lady Gaga IS much more successful than Madonna. Sure, 20 years ago Madonna ruled, but that was 20 years ago. Her time is up. I honestly just think she's bitter now.
And to the answer above: I don't think you realize that Madonna is older than 50. Lady Gaga is 25. Of course Madonna has more experience. Unless Gaga was famous worldwide ever since she was -7 years old, it's impossible for her to have more experience than Madonna.
Gaga has 17.2 million followers on Twitter. I'm watching a show/interview right now, actually. It's called Gaga by Gaultier". And it's beautiful. I don't see any shows about Madonna right now. She's not even in the news anymore. I literally don't even hear about Madonna anymore, if I ever do it's because they're talking about her daughter or something irrelevant. Madonna is done for. It's all about Gaga now.
Fan since '07.