So what’s going to happen? Let’s review what we know and what’s been rumored.

What we know:

• The “roadmap” will cover the iPhone software developers kit (SDK) that Steve Jobs had hoped to have in developers’ hands last month. If what is revealed is a beta SDK, as rumored, there will widespread disappointment.
• Apple also promises “exciting new enterprise features,” which has got the attention of IT managers and the employees who have to work with IT to get corporate support for the iPhone.
• The SDK will almost certainly not include support for Adobe Flash — one of the current limitations of Safari on the iPhone — given that Steve Jobs declared, at Tuesday’s shareholders meeting, that it”performs too slow to be useful” on the iPhone.
• That Jobs has promised “a lot of apps out there this summer,” including games.
• That native iPhone apps will be written in Cocoa, Apple’s proprietary development environment. When asked about a blogging application for the iPhone at the shareholders meeting, Jobs told the shareholder that if Apple doesn’t address his needs, he should learn Cocoa and write his own app.

What has been rumored:

• That the SDK runs only on Macs running OS X Leopard and is facilitated through an enhanced version of XCode made available to members of Apple Developer Connection. (see here)
• That iPhone applications will be allowed to use both EDGE and WiFi for data. (see here)
• That Apple will have the final say on which commercial iPhone applications are sold, will distribute them through iTunes, and will take a small cut of the proceeds. (see here)
• That iPhone freeware is unlikely to be subject to much if any scrutiny by Apple. (see here)
• That this SDK will not support applications that access peripherals through the iPhone dock connector. (see here)
• That the final version will be released at the World Wide Developers Conference in June. (see here)
• That there’ll be lots of demonstrations of business applications from the likes of IBM (IBM), Salesforce (CRM) and Microsoft (MSFT). (We’ve already been contacted for pre-SDK coverage from several firms that make apps for business, including SAP.)

How much of this will come true? We’ll find out soon enough. Jon Fortt will be covering it for Fortune.com. Several Apple sites will be liveblogging from Town Hall, including Engadget, Gizmodo and Ars Technica’s Infinite Loop.