To Upgrade or Not

Recently many previously free services have been offering upgrades. This past month I have received emails from LinkedIn, Pandora, and the New York Times. Is this a sign of the times and a change brewin'? Currently these three companies are offering free versions that work just fine for most people, but could these previously free services be disappearing for a monthly subscription? Would charging for usage help or hurt the company?

Currently the NYT is offering a certain amount of information for free, and once that amount of information is consumed the consumer will be shown different pricing options for upgrading their usage. For Pandora users they can use the free version but have banner ads as well as commercials. The upgraded version offers better quality audio, no ads, and unlimited listening hours. But honestly, how many people listen to Pandora THAT much? For LinkedIn the cost is quite astronomical, ranging from $20 - $75 a month. What do you get? Bigger search results, the ability to see anyone's expanded profile, and guaranteed responses 3 - 25 users depending on the package selected.

Do you currently pay for any of these services? Is it so amazing you can't live without it? Let me know :)