One of the rootsweb mailing lists to which I subscribe has had a discussion regarding Ancestry.com and the "inaccuracies" in its data. After reading some back and forth, I ascertained that the biggest gripes were not regarding Ancestry's original records, but rather the member submitted data. Below is my response/addition to the conversation:
Ancestry, as well as similar sites like Footnote and NewspaperArchive, is primarily a for-profit, original record repository. Personally, I use them on a daily basis for a variety of databases: census, birth and death indexes, WWI and WWII draft registrations, passenger lists, and so forth.
Yes, I would rather have access to these records for free, but if they use the fees they charge to digitize even more records and make them available to me then I am all for it. In short, if they were not in business, my research would become a -lot- harder.
Ancestry does provide both free and paid member areas for individuals to share their research. That data will only be as reliable as the individual that submitted it. And it should never be a "source" for your information, only a suggestion on where to seek out the original records. I would not imagine that Ancestry would ever take any sort of responsibility over the inaccuracies that individuals may choose to submit.
There are other alternatives, in some cases very superior ones, to both finding original records and to the sharing of our research. For those of you who are not familiar with it, FamilySearch.org is an -excellent- free resource. They are adding millions of images on a regular basis as they digitize the microfilm that has been acquired by the LDS. They also have very informative and in-depth resource guides to virtually any location worldwide. I use FamilySearch perhaps more than Ancestry.
There are also some great options for sharing your research with others, in a way that you can control and is free. WeRelate, WikiTree and Geni.com are all sites where you can add information about individuals you are researching, including source citations. Each has their benefits and drawbacks. One factor that they all have in common is the ability to link your work to others.
If you really want to have control over form, content or even who has access, you can also try your hand at blogging. The two biggies in that realm are Blogger and WordPress. If just starting out, I would recommend using Blogger. It literally takes under 2 minutes to setup a new blog and creating an entry is as easy as typing up an email. I have seen a lot of beautiful, quality work being uploaded to researchers' blogs.
To find some examples, you could do a web search for "genealogy blogs" or visit Geneabloggers for a comprehensive list. Think of it as a Cyndi's List for genealogy blogs.