AVAST has a tradition of developing their own innovations, so AVAST incorporating the behavior blocker of AVG into their product is a major change.
AVG had a history of buying companies to add components to their Anti-Virus:
AVG take overs I recall
- Ewido (anti-spyware)
- Primary Response Safe Connect (a behavior blocker, which may still form the core component of the current behavior blocker)
- Linkscanner surfshield (a URL checker and a script analyzer to filter out javascript code patters which were used in exploit kits the script filter was very advanced at the time, but when other AV's were copying this type script filtering, the exploit writers started to obfuscate their code, reducing the effectiveness of script filtering/sanatizing, luckily today all webbrowsers apply script sanatizing which makes it harder to for malware writers to obfuscate code and increase the effectiveness of script-filters again).
They will probably focus on different market segments in the future. So for the coming years I expect them to share components while on the same time offering different packages to different market segments.