He doesn't show Opera doing a MITM for HTTPS traffic. Infact, from Operas Privacy Policy regarding their boost:
Privacy in Opera Turbo
When Opera Turbo is enabled, the service will compress network traffic, thereby increasing download speed and reducing data volume. The service requests normal Web content through an Opera Software proxy server. Opera Turbo will exclude Web pages located on an intranet or by using secure connections (HTTPS). Opera collects IP addresses, usage patterns, and the point in time at which the service is used for the purpose debugging, maintenance, optimization of the service, or maintaining the customer relationship. Analysis of service usage is conducted by aggregating data, anonymizing individual identities.
this clearly states that HTTPS traffic is untouched....Compared to Nokia which is rewrapping your encrypted data. whats the point then?? I'm not connecting to https xyx, im connecting to nokia, who is then connecting to https xyx....that is so stupid. A single compromised certificate or proxy server would expose enormous amounts of data.
Nokias privacy policy makes not a mention of intercepting HTTPS traffic. Good job to Opera to following their privacy policy.