The other day I saw someone behind me watching Avatar the Last Airbender. It put a smile on my face knowing that people still cherish those shows.
On a serious note though, I think in the current generation people don't care about it that much. Alot people (at least those in my age) tend to see cartoons and anime as being another medium of entertainment, and it has began to lose the stigmas surrounding it, albeit very slowly. While the medium was initially meant for kids, it has expanded outside it's general demographic to appeal to other audiences.
I think calling those who watch cartoons or anime childish is a bit outdated in my opinion. You really only see that happening when it's a cartoon/anime that isn't very popular in your area. (For example, like how Family Guy, The Cleveland Show, South Park in the West are not regarded as childish for simply watching them).