As online music streaming services continue to grow and evolve and summertime tunes start to fill the air, we thought it would be a good time to sit down with Thomas Chau, programming and product director for AOL Radio, to help us pick some new music and also better understand what makes AOL Radio unique.

Announced last fall, AOL Radio's partnership with Slacker Radio combines Slacker's advanced technology with the acclaimed original programming of AOL Radio Music Directors and DJs. In a phrase - it's the best of both worlds. "Our 200+ stations are managed by our team of seasoned music professionals who have years of expertise in the genres that they manage," said Chau. The size of Slacker's library, which houses millions of tracks, and real time customization also make AOL Radio unique. "Our platform allows us to take the very latest listener song data that we read on a daily basis, and see right away how users are responding to music. We then make adjustments to our stations depending on how people are reacting. Are users listening to the song in full? Or are users skipping right away to the next song? Are they favoriting the song, or are they banning it? These factors - along with our own instincts and tastes - help make our curated stations the very best they can be."

AOL Radio's "New Music" stations (like New Pop First and New Hip-Hop First), introduce listeners to the next big thing and features new artists and songs even before they're available for sale or played on competitors' stations. To fit all audiences, AOL Radio also comes in three flavors: Free, Ad Free and a full on-demand music service (launching in June) available on web and mobile.

When discussing AOL Radio's latest offerings, new countdown stations, Chau becomes sentimental. "I remember watching MTV as a kid and sitting through wacky video countdowns, or listening to countdown shows on my local radio. Similar to how blogs create Top 10 lists or photo galleries on a regular basis, AOL Radio is bringing back the radio countdown but in a 2.0 way... A good countdown takes you on a nostalgic journey, so to speak, from beginning to end and that's what we hope to accomplish with these countdown stations this summer."

How will these countdowns differ from those of Chau's youth? First off, "listeners don't need to sit through the whole thing at once. They listen to however long they want and return at a later date/time and it will start back where they left off. They also don't need to start listening at a specific time. The stations are there for them on-demand to start or stop whenever they like."

Already, the Top 50 Boy Band Songs station has received overwhelming fan support on Twitter, "They're chatting about what they're hearing and talking about songs they had forgotten about, something we don't see happen with our regular stations." This is not the first time that the social media product has helped connect AOL Radio with its listeners. "A few years ago when Twitter was growing and relatively new, I decided to do a Twitter Request Day to help grow our social media presence. We told our listeners that on a certain day, we would play any song that was requested to us on Twitter. The more votes a certain song got, the more often we would play it. And so during the course of 24 hours, we saw record labels, artists and die-hard fans rallying to get their songs as many votes as possible. Artists like Justin Bieber, Natasha Bedingfield and David Cook tweeted to their fans to get their songs requested. We saw tens of thousands of requests during that day and within the first few hours, we saw that #AOLRadioRequest was a trending topic, according to a third party tracking service." Chau cites this accomplishment as one of his proudest moments.

Chau personally programs the pop and dance stations and manages various other aspects of the product, such as customer feedback, product development, product troubleshooting and social media outreach. Outside of work, he listens to even more music, plays video games, explores new restaurants and is "also searching for the best lobster roll in New York City."

And new music? Chau also offers his predictions for summer's big music tracks which include, "Usher 'Scream' and Calvin Harris & Ne-Yo's 'Let's Go.' There are some new artists with debut singles that I expect to be big hits, including Rita Ora's 'Party,' Cher Lloyd's 'Want U Back' and Sammy Adams' 'Only One.'" To hear all of these tracks visit the Fresh 40 station and to learn more about AOL Radio, read a product review here. Also make sure to check out the newest AOL Music Sessions featuring hit boy band, The Wanted.