I've been playing with Google+ for the past few days now. Personally, I'm really digging it. If you work in or around digital (marketing, design, etc..) or if you own a business you would be a fool to ignore Google+. It's no doubt for the geeks right now, but that will change.
Some initial thoughts and things I like:
• The ability to segment relationships into groups.
• Trimmed down user interface.
• Integration with other Google services.
• I trust (loosely) Google with my data more than Facebook.
• The way they integrate updates/ the newsfeed by group.
Lastly, and probably most obvious and important (if you're a marketer, business, etc.) is that Google will more deeply integrate social signals into how they are determining search results. If you are marketing anything online that depends on ranking high in the search engine results pages you should probably pay heavy attention to Google+. They will no doubt be pulling signals from Google+ to determine how sites rank in the search engine.
These signals might be the influence one's social graph commands, number of times things are +1, etc...
I can foresee a lot of first mover advantages that might unfold for those that are onboard early and understand how to take advantage of the product.