Are these guys going to overrun my tank and start eating the plants? At
first I thought that they were trumpet snails, but judging by the jelly
like
eggs, they're pond snails. Different websites say that they are to be
avoided, and others say they'll stick to the algae. Any thoughts?

I just leave them alone... the smaller snails seem to only pick at stuff
that's on it's way out, and may even help with algae control, substrate
aeration, digest uneaten food... if they are eating my plants, its easy to
grow the plants much faster than they are eating them. I see no reason to
keep loaches or "sterilize" incoming plants to avoid this... one vote for
let the snails be! (and mine are pond snails, little jelly eggs with
white centers)

Cheers,
Jeff Ludwig