Is LinkedIn (NYSE:LNKD.DL)  CEO Jeff Weiner smarter than Mark Zuckerberg? It's an unfair question, I know, but I'm honestly starting to wonder. Facebook (NASDAQ:FB) is losing partners and annoying techies even as LinkedIn is taking user engagement to new levels.

It's latest ploy: LinkedIn Contacts, a new service that aggregates your various email accounts and address books into a cohesive whole that organizes by name, tag, company, title, and even location. Here's a worldwide look at my network of 1,000-plus contacts:

Sources: LinkedIn and Google Maps.

Impressive? Pathetic? I suppose that depends on your point of view.

Either way, LinkedIn is hardly the first to dabble with building a better address book. came to be largely as a result of needing a globally accessible contact database whereby salespeople in different territories would get access to the notes and details of every prospect and account.

Google also has a customizable address book attached to Gmail, while Microsoft has Outlook. But these are self-contained apps that are only as good as the data you feed into them, and maintaining a large database of contacts gets exhausting fast.

Aggregating existing data seemed like the best approach for me, and in years past I tried 37signals' Highrise (great, but too expensive for a solopreneur) and Cobook (also good, but too slow).

LinkedIn Contacts comes just short of the richness of Highrise but adds private messaging between LinkedIn members, a built-in social network for sharing information, groups, and a curated news platform:

Introducing the New LinkedIn Contacts from LinkedIn.

Far as I can tell, LinkedIn isn't yet including Contacts among the premium add-ons it asks subscribers to pay for. Yet I suspect it could: Revenue from premium subscriptions soared 79% in the fourth quarter.

Therein lies the  difference between LinkedIn and its peers, I think. Whereas Facebook and Twitter are working on ways to create value for advertisers, LinkedIn is working on ways to create value for its members. Contacts is the latest try, and it's a good one.

Do you agree? Disagree? Let us know what you think of LinkedIn's premium services and whether you'd buy, sell, or short LinkedIn stock right now.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.