It's definitely worth a few quid, I've thought about putting that one on.
Wouldn't bet on him being the next one though as if England don't qualify or get knocked out in the group stages at Euro 2004 Sven will be under pressure and Adams won't be ready.
He needs to keep Leicester up or even better mid table, then he'll get offered the job at a big under-achiever like Spurs or Leeds and once he's succeeded there he'll be in the running...
So put money on him being a future England manager.