VMware are announcing this week that there is now a third option available for a VCP3 holder to update their certification to VCP5, here's all three options:
1. Attend vSphere 4: What's New > pass VCP4 exam > pass VCP5 exam.
2. Attend vSphere 5: Install Configure Manage > pass VCP5 exam.
3. Attend vSphere 5: What's New > free vSphere 4: What's New e-learning (optional) > pass VCP5 exam.
I've updated this blog post to include the new path: