I can't prove it, but the following table is suggestive that there is significant new entrant/non-incumbent activity over a wide range of licenses, most strikingly in B Block. This table tracks numbers of bids per license by block (and the licenses are further sorted by total number of bids per license) over rounds 1-26 (round 27 will open on Monday).

What is interesting is that there are large numbers of bids on a wide variety of licenses of differing population sizes. Since the incumbents traditionally focus on the higher population area licenses in each block, the relatively high levels of competition over licenses of significantly differing population size suggests that anonymous bidding has emboldened new entrants and non-incumbents to compete more intensely than in earlier auctions (which also accounts, in part, for the larger revenue stream indicated by the higher provisionally winning bids).

It's not much evidence, but it is an interesting datum, and it appears to show a pattern consistent with higher levels of competition over a wider range of licenses.