Well there are a few reasons why I'm really enjoying this series.

1. The soundtrack

I really enjoy the classics which is used throughout the series. Great tracks which have been used well to emphasize the mood at the time.
The classics never die :D

2. The Setting of the movie back in the 70's

I love the 70's setting, it's like going back in time. Things were so different back then.
Wish I grew up in that time period.
I guess I am old fashioned though so I guess thats why I like it so much.

3. The storyline

I'm really enjoy the storyline. It has some great theories, like alternate dimensions, telekenisis and telepathy.
I guess it's the sci fi nerd in me. lol

All in all I'm really impressed, this is a great all round series.