My big 5-0 was last year - last December actually.
I didn't make any plans for a trip or anything like that BUT my DH planned a surprise birthday party for me. It was a total surprise - I thought I was going to an engagement party for some friends at a local restaurant. Still amazed at how well he pulled off both the party and the surprise. The party was timed to be about a month before my birthday, so maybe that contributed to the surprise aspect. And, I am often rather oblivious to goings-on around me anyway. 
As for actually turning 50, I honestly don't think it has/does bother me. Sometimes I am rather startled to realize that I am actually 50, but more in terms of 'how did that happen' and 'where did the time go'.
Serendipity
"So far, this is the oldest I've ever been....."