And if I'm not the first to suggest that Ancestry digitize the St. Louis death records, add my name to the list of supporters. These records seem to be a little misunderstood by those that have never viewed them and they are probably one of the top lookup requests on message boards and mailing lists for the area.
Here's an example of the information Ancestry provides:
Name: August Lankan
Death Date: 16 Jun 1890
Address: 314 Marion
County Library: RDSL 33
Missouri Archive: C 10389
SLGS Rolls: 323
What you don't see is the cause of death, place of birth (very generalized, e.g., Germany rather than a town name), approximate age, cemetery, undertaker and physician. (The cemetery is often listed in Ancestry's database, but some entries lack this info.) I may be leaving out a couple of headings but that's basically it. While these are somewhat primitive death records and not the most useful for connecting the dots (the deceased to another family member via an informant or the names of parents), I don't see why anyone wouldn't want to have this information. At the very least, it can be used as a jumping off point to look for an obit, family plot at the cemetery or used with directories to see who was living at an address at that time.
As I mentioned, these would be fantastic records to digitize. Actually, so would the St. Louis burial certificates, a document used starting in about 1881 or 1882 that has a lot of the same information. To me, those two record sets would be just about as valuable to me as the census records, which is the main reason I have an Ancestry subscription.
The burial certificate is a single document, while the death records are actually a register or log of entries that spanned two pages on a single line. Personally, I prefer to have a copy of the burial certificate just because it's easier to file and they often print better from microfilm than the death register. Over the years, the burial certificates started to become more and more like death certificates. Some of the forms even say so at the top. But if you go to a local library and look for pre-1910 death certificates, you're looking under the wrong heading.