Innovation is contained within a few isolated groups at T-Mobile. Everyone else is expected to merely follow along and just not rock the boat. As a result, people who are creative and pride themselves on effecting change would likely find T-Mobile to be a bit stifling and slow moving. What's worse, this is actually a problem that has been discussed at company meetings, however despite the expressed outward desire to address this by top level execs you will often see the folks in the rung beneath these execs focus on the status quo unless the idea comes from the top.
An additional challenge is that despite the fact that T-Mobile touts internal mobility as a big plus for working there many managers seemingly ignore internal requests and often fail to process interview requests for qualified candidates. As a result, I would strongly advise candidates to lower the value they place on moving around as an option because many managers simply ignore interview requests.
Also given the current state of T-Mobile's business where the company has already frozen pay raises for 2009 and had started to cut back Travel and Entertaining budgets as early as Q2 2008 I would warn candidates that many of the perks that you might hear about at T-Mobile will likely not be the case going forward. As trips, retreats, group events, etc will likely receive very little funding until their current economic situation rights itself.
As a side note, one should not kid themselves in that there are definite tensions in the organization. Retail is often at odds with the online store and the dealer channel. Some marketing teams do not like each other and have leaders who actually despise each other.
