Actually, annuals tend to bloom continuously through a long summer season, whereas many perennials bloom only once. The difference is that the annuals die over the winter in a given climate, hence lasting in the garden only one "year." Note: Annuals may be perennials in the warmer climates of their origin.
Just being annoying pedantic. But an "annuals"/"annals" gaff would put me off, too. To what extent would depend on how many books the agent has sold, and how well. If he's a firecracker, he can call my marigolds anything he wants.
The Wordsmithsforge website confused me. Is it offering to put work up in audio form? I tried to look further into the site, but got error messages for all but the home page.
Another thought: "Annual" can also refer to a once-a-year publication. I'm not sure, though, that this is what the website refers to.