I've not seen this show myself, or at least not much of it.  I take it that Theodore Tugboat more or less is to boats what Thomas the Tank Engine is to trains?

Makes me wonder how long it'll be before there's a crossover...?

Correctamundo. Heck, the executive producer of this show used to work on Thomas the Tank Engine, as well as the "prequel series" in the UK (with only 13 episodes sadly) called TUGS. Theodore Tugboat had 5 Seasons and 130 episodes, thus it was fairly more successful than TUGS.

Who knows? I'd love to see that happen too. Tho the timeline differences of the two shows might not make that possible.