There’s a thread at Casinomeister where some individuals who bank with Wachovia and Washington Mutual have been experiencing NETeller transactions be declined per the bank’s policies.
NETeller would send the transaction, the bank would decline it, then NETeller would send it again disguised as something else, and it would go through. The problem is that they would ding the customer the $30 NSF fee because of the initial decline.
http://www.casinomeister.com/forums/other-complaints/13646-big-neteller-problems.html
So despite the lack of a gambling flag on ACH transactions, banks already have the capability to detect and decline NETeller transactions.
The part that is worrisome is the possibility that ISPs are going to block access to NETeller and similar sites.