The sound on Beats is actually good; much better than what most people have with their headphones so most users will experience an improvement by switching to them.
The problem is that the cost:sound ratio is poor; you can find cheaper headphones with the same quality and you can find much better headphones for the same price.
Sound is a very objective measurement so I won't go ahead and say that beats sounds "better" or "worse". However (I can't seem to find the link now) on many audiophile forums Beats have been measured to skew to better frequency response in the low range. Therefore they will sound more thumpy but without warm mids and crisp highs. Beats has engineered their headphones this way for a specific marketing demographic, I just don't know if this is what the majority of Apple customers want and interpret as good performance.
That may be the case, but consider that most consumers are probably currently using the <$15 earbuds that came with their phone. When those users switch to Beats they will get a much better sound experience, even if the frequency response is skewed.
I'll continue to recommend sennheiser over Beats, but I think the primary objection to beats should be their cost, not their quality.
This is a very important thing to remember: people always talk about how 'audiophiles' hate Beats headphones and would recommend a better-sounding, worse-looking and sometimes more expensive option.
The people buying Beats are people upgrading from their free headphones that came bundled with their phone, or the $15 ones they picked up at the supermarket.
Those are $30 headphones and I _love_ them. I use headphones 10 hours a day and it's always the apple ones. So comfortable, just the right amount of noise-canceling so I don't have to remove them to talk to people, and they sound good to me.
Beats are also very comfortable. Not much is said on headphone comfort in reviews and comparisons but it's very important for me.
The skew is exactly what Dr. Dre's fans, and other pop fans, want. They are made by a former gangsta rapper turned pop rapper. Who can listen to Dre without a trio of 12" subs rumbling their car or house or the dancefloor?
I have had Beats for 2.5 years. I like a lot of rap, and rap sounds awesome. Nicer headphones may have a better sound for a more broad range of music - but they don't replicate the 808's and fat basslines on Novation.
This isn't even close to being on topic, but I upvoted you because 'fat basslines on Novation' reminded me of the Wu Tang Clan! Triumph is a great song...
Beats Headphones are fashion items, which is really most of the innovation they provide: making a normally geeky or tacky piece of equipment into something stylish.
What it looks like to you is besides the point, it's how they look to the people around you.
I know that, and I know that's important for some people. But for me, my aesthetic experience is not changed by how headphones I wear look, but just by how they sound and how comfortable they are. I spend most of my time wearing headphones alone, and very little of that in front of a mirror.
And still: any headphones, even the prettiest ones, look kinda lame in comparison to not wearing headphones. This is my personal preference of course; if I was worried about looking good rather than hearing good sound, I'd stick to little in-ear ones.
The problem is that the cost:sound ratio is poor; you can find cheaper headphones with the same quality and you can find much better headphones for the same price.