[BrianG]

Antenna wire: Most antennas are more sensitive when being used to transmit, but sealing the bare wire is a good idea. Folding it over, putting a cap on it, and heatshrinking is a good idea.

Motors: No matter what, you're gonna get water in them. Don't know what would make Titans more sensitive than any other motor, except maybe the quality/composition of the brushes.

Batteries: Tough call on that. Best bet would be to encase them in a rubber balloon or something like that and seal the end. However, this would impede cooling, so watch temps. A lexan case could work too, but probably tougher to completely seal up.

Connectors: Don't worry about them. They're gonna get wet, and any waterproofing solution will make connecting/disconnecting them a PITA. Yeah, you may get corrosion on the non-gold plated parts after a while, but they are cheap to replace.

I take it the ESC is waterproof? BTW: there is a difference between water-proof and water-resistant. One means it's ok to submerge, the other means it's ok to splash water occasionally. If you seal up the ESC to be safe, watch cooling...