What does "pre-alpha" mean?

We're calling the version of FeedBurner that we launched today a "pre-alpha". What does that mean? Well, it means that we think we've reached a point in development that would really benefit from having a number of informed users in the syndication community evaluate the feature set and services that we're offering. But we're definitely still in development mode: debug logging is still turned on, we're not 100% redundant, we're still tuning the databases, and we'll probably bounce the servers once or twice a day to fix bugs and introduce new features. Once we can guarantee 100% availability and ensure total data integrity, we'll re-launch as a for-real "alpha".

In terms of the feature set, I just wanted to mention a few things that aren't there yet but will be soon -- issues that have come up in mailing lists and wikis in the syndication community that we're aware of:

• Our resource retrieval component doesn't respect the aggregator refresh hints yet: this includes the ttl, skipHours, and skipDays elements (in RSS 2.0 family of feeds), the syndication module elements, or the HTTP Expires header. Basically, we treat all source feeds as having a ttl of 30 minutes, so we shouldn't hit your source feed more than once every 30 minutes. Full syndication hint support is coming soon.
• Character encoding is not being preserved in all cases. Many times we'll re-encode the burned feed as UTF-8 instead of the character encoding used by the source feed. We're aware of it.
• Feeds must be well-formed and valid. This has always been an interesting issue for feed aggregators and clients, and has had a revival recently in the Atom community. At this point, FeedBurner is using a standard XML parser to parse source feeds, which means it won't be able to process less-than-perfect feeds. Adding a service to bring invalid feeds up to snuff is on the to-do list.
• We're still working on handling content encoding the right way in all cases. This means that sometimes we might treat html in the <description> element of an RSS 2.0-family feed as plain text, or that we don't handle <content type="multipart/alertnative"> elements in Atom feeds correctly. On the radar.

We're going to slip in new features and capabilities throughout this pre-alpha period, so watch this space to keep up with the latest! And thanks a lot for giving this a try and letting us know what you think -- we respect your opinions.