One thing you may want to remember when thinking about lists versus libraries is that a library allows you to create metadata around a single document so one document is the item in the list while the lists allow you to have multiple attachments in regard to metadata that is the item entry. The limitations of the attachments, like Laurie mentioned above are that you cannot do versioning on attachments in lists. However, you can still search by these attachments and find them using either the metadata (list entry) or the text or title of the attachment. If you are using 2010, the other difference is that you cannot tag or place notes on attachments while you can on documents in libraries.
If you are using 2010 also, you may want to consider document sets as well, this allows you to collect the same metadata for all of the attachments. Another option for you if you need multiple documents and versions around them for a specific item or need.