Hi Andy,
I suppose it will eventually be used for that, but it only works if you or another Tile user is 50-150ft away. Since bikes are so mobile, knowing where your phone last "saw" your Tile isn't going to help much.
The Tile "community" will have to be quite pervasive for this technology to work on that scale.
Unless I'm missing something?
And besides, who wants to wait until next (presumably northern) summer to get their tiles?
That's a showstopper for me.
Sam