1. Client Application is renamed as P6 Professional (EPS, OBS, USERS and Security, etc.. are removed in P6 Professionl) 
2. There is no In built workflow with primavera web, we have to install Oracle BPM and need to configure with P6 web 
3. There are no default Reports available in primavera web, You need to install Oracle BI publisher, P6 Reporting database, BI Publisher need to configure with Primavera web, and reports will be taken from Reporting database (ODS) not from Primavera Database(PMDB) 
4. Methodology management Removed in P6 R8 version 
5. P6 analytics, OBIE and reprting database (star) need to be installed for Advanced reporting which is same like previous version(P6 V7) 

Regarding to reports, in Project Management Desktop Client there's a new option to store the report in html format and automatically create a document definition linking to a public location folder. Saving this to a file server (users, folder permissions, scheduled backups, etc), allows you to view the report at WPs & Docs.