As part of the Update Roll Up 12, Microsoft released Updated User Experience for Sales and Customer Service. This will give an option to work with the forms without using much pop ups, but main problem is we cannot control the forms with Java Script. This is a limitation as of now but we can expect some enhancements in near future or in the next releases.
In the below Lead screen shot user can work on Lead through Contact and Opportunity without having a pop up. This is so nice of CRM.
Microsoft has given the flexibility to go for it or continue with classic UI. This can be installed from Product Updates section under System Settings, once installed this can not be rolled back but user can inter change between classic and updated form at any time while accessing the forms.
Here is the video from Microsoft on Polaris/December 2012 Service Update