Are you talking about Deloitte & Touche Tohmatsu, the financial consulting company, or Deloitte Consulting, the tech consulting branch?
I was a contract employee for the latter. My experiences were mixed. I really liked all of the people save 2, which is a very good thing considering I worked there for a little over 5 years. However, I really had a lot of problems with the way they went about things, in that ultimately the bidding process and money almost always came before product quality. Many times I felt ethically conflicted because my client was the state, aka taxpayers were paying for stupid crap. Furthermore, I felt that some of the consultants were treated poorly in terms of the amount of work and expectations, even though the benefits and community were great.
But, one of the 2 people I didn't like was who ultimately drove me to look elsewhere. He was a young "hot shot". He was great in some ways, but he was the type that thought he knew everything even though his experience was largely in outdated systems. When I complained about the lack of a skilled web design team on a huge project that was costing taxpayers millions, he accused me of being lazy for wanting someone else to do my job [Edit: note my expertise is not in design, it's infrstructure, architecture, etc.. I was just "the best available" because their policies sucked]. That ultimately is the mentality.
So, great people with rare exceptions, bad policies, overall left a bitter taste in my mouth even though I really like many of my former coworkers and consider them friends.
I don't have much experience with the financial branch.