Is there an online community less juvenile than myspace but less business like than linkedin in which adults "only" blog, share photos, upload music and send messages to friends?

Try Facebook

But its not adults only,
But its not as much like colourful backgrounds

Facebook | Welcome to Facebook!

You canf ind old friends easier on it

There are many free blog sites that one could check out and possibly join. blog site - Google Search

I don't know how old you are. But, I joined eons. Eons: The first and largest online gathering place for people lovin' life on the flip side of 50! It is for people 50+.

There is also https://www.blogger.com/start I don't think that there are a lot of children on it.

Check out iYomu | Social Networking for Grown Ups - it's a social networking site designed just for grownups. The communities seem to be on sensible topics - not juvenile music and movies and stuff.

Better start your own blog and let people juoin it and comment.
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