Just thought we'd let the droves of paranoid upgraders know in on a small bit of good bad news. Yes, Apple did already release a new version of iTunes tonight, 7.4.1, and we tested to see if said update "fixes" the ringtone-renaming hack (if you really want to call it a hack) that lets users supply their own ringtones sans Apple's $0.99 fee. Breathe not so easy: it may be legal (probably), but the hack did not continue to work just fine for us. More below.
Update: So yes, our previous ringtones carried over and we were able to add new renamed ringtones to iTunes -- but our readers are right in that 7.4.1 DOES block the renamed ringtone workaround moving forward. Our initial syncs went unblocked, but only until we tried to add new ringtone files. Once you actually attempt to sync new renamed ringtone files, well, then you're in for a heap o' pain (see above).