He was charged with making the Android Market competitive
Chu will be replaced by Jamie Rosenberg, who currently works on the Google Music team. Google Music will be merging with the traditional app marketplace to form Google Play, and Rosenberg will now be the one in charge of making sure people gravitate toward that platform.
The problem is that the Android customer base remains fragmented. That is the key solitary issue that has prevented almost any developer-friendly initiative from working.
The next version of Android, Ice Cream Sandwich, is supposed to be a big refresh button for the platform, where device manufacturers will need to adhere to very specific hardware specifications.
Unfortunately, we've heard this kind of rhetoric before. Android 3.0 was supposed to define a universal standard for Android tablets but there is fragmentation there already.
And before even 2% of the Android user base gets version 4.0, there is already talk of version 5.0. This kind of stuff just makes the entire process of developing for Android a headache.
Chu had the passion to change that mindset but wasn't able to pull it off. We'll see what Rosenberg brings to the table.