Different wallets may be used for different purposes. When a notification is triggered, we get the TXID but don't know which wallet is involved. It would be useful to have different walletnotify actions depending on which wallet is involved by the transaction.

It could be used like (bitcoin.conf):

walletnotify.walletname=action %s

Or maybe a more simple and flexible (dynamic-wallets compatible) way:

walletnotify=action %s %w

where %w is the name of the wallet. This way, notify action (and not Bitcoin Core) is responsible for choosing the right action depending on the wallet and it is easier to RPC query the good wallet (ie gettransaction).