1. Google will definitely pay well...they have tons of cash, just check their balance sheet. Plenty of cash even after paying all their employees great salaries.
I wouldn't say Google competes with GS for analysts. If you're talking about the Corp Dev branch...they usually take folks who have been analysts at the likes of GS because of their banking experience. However at the entry level, they are not really competing for the same type of candidate.
2. It's possible to switch into Accenture consulting now - you'll need to network your way through and impress during the interviews.
3. Not sure about this one.
There are a number of articles on our partner site mergers and inquisitions about the back office. Try this one
It's true, many people don't know how the corporate world works at banks until they finally get there and are pigeonholed. Moving onward requires a lot of networking. It's not easy, but it's possible. After a few years, some people consider rebranding themselves through business school. It may make sense to take the GMAT and take it as an "option" for your future career
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