Here in Germany, T-Mobile slashed prices somewhat dramatically in an April-to-June promotion. Maybe they've got too much inventory ahead of the introduction of the new iPhone. Interestingly, there's now a new low-cost plan that does not offer unlimited online access.
An AT&T memo is asking sales employees to schedule any vacations "before June 15 or after July 12" because of "an exciting Summer Promotional Launch" with "heavier than normal customer traffic in our stores..."