Usually, the big 4 or whatever the number is, on any given day, used to be a big selling point for developers and engineers, who consulted under their brands. I know one of my previous employers used to directly hire consultants sent to us from one of those consulting firms.
Although it is not as much prevalent nowadays as it was in the past, if you get on board with a consulting company with a well known name, it will help you open the doors in the future. Working for consulting company shows, you are flexible, can learn fast and be very agile, as you potentially change clients frequently and no two clients are the same.
IT consulting companies, do not have as much agility as the accounting firms as far as moving you from one assignment to another. Accounting firms specialize on audits and those need to be done in a short period of time like few months tops. IT consulting projects are usually working on very large scale projects for long duration of time slices. Both have their positives. Neither is to balk at if you are looking for work and gain experience in my opinion