Five months ago the Android Market had 10,000 applications. Today, as reported by AndroidLib, Android Market has doubled in size since then and hit the 20k app market. Pretty astounding, but still miniscule in comparison to Apple’s iPhone App Store.

But the key in this case is about momentum and NOT competition. According to IDC Research (via GigaOM), Android Market growth will outpace that of Apple’s iPhone App Store in 2010. But that doesn’t really matter… one of these operating systems is never going to “beat” the other. They’re both destined to sit on top of the mobile kingdom, each wearing a different type of crown and reigning over a different land with different rules and different values.

The important factor is that each operating system fuels growth and innovation, but also manages that growth appropriately. With 100k+ apps in the iPhone App Store it is nearly impossible for users to find what it is they are looking for or to find things they might enjoy. Unfortunately for Android users, despite having to sift through far fewer apps, the task is even harder as no great system of browsing the possibilities as been put in place.

It is nice to note that more than 60% of Android Applications are free. That’s at least 12,000 free applications or games. And while sometimes the “you get what you pay for” cliche rings true, there are a LOT of great downloads that’ll cost you absolutely nothing.

Like Google, I’m sure many of these devs offering up free software hope that mobile advertising is the next big growth area and if they’ve already got a large mass of users, profiting will come naturally.