The EULA limits you to 1000 static maps created for your pages.
So in theory you're okay if you do it for only 1000 days (and upgrade to the next version during that time). No I don't know when the next version is due, but it is probably within 2 years.
I'm interested in what you're doing with birds and maps. Is this as a part of an organisation like Audubon or RSPB?
My wife is the current President of the local (Dallas) Audubon Chapter, and we've discussed the possibility of using MapPoint for displaying/analysing bird count data.
She also does a lot of field research at a local preserve, but she requires a 'proper' GIS for that - she is plotting tree counts on a 10m grid!
Richard