I think the concern here some posters have is of the phenomenom of incrementalism.
The general idea is that once goverment gets a new power/ability/legally admissible tool, it builds on it. It usually starts with something no one disagrees with (child abusers, drunk drivers, 'the children'), expands some to something fairly easy to get legal cover for (drugs), but then at some opportunity in the future, under a future administration (can you imagine an HRC admin, or a kerry admin putting 3 justices on the court, etc.), something many defenders of this ruling here would never support today suddenly gets slipped in.
Forfeiture laws are another good example...now that they are apparently 'constitutional' for some crimes, it is just a matter of interpretation under the right court to expand them. I think it is pretty clear that if they are OK for some crimes, there is no clear legal reason for them not to be OK for any felony if congress wants to go that route.