1 person found this helpful
If you purchase FB 3, you'll be able to extend your FB 4. However, when FB 4 ships (expected at the end of '09), you would need to buy an upgrade for FB 4. Hope that helps.
From our FAQ
Q: If I purchase Flex Builder 3, am I eligible for an upgrade to Flash Builder 4?
A: Adobe has not yet announced the ship date of Flash Builder 4. To be eligible for a free of charge upgrade to Flash Builder 4, you will need to purchase maintenance along with your purchase of Flex Builder. You can purchase maintenance with your Flex Builder 3 Standard purchase for an additional $99 US which makes you eligible for a free-of-charge copy of Flash Builder 4 Standard edition when it ships. You can purchase maintenance with your Flex Builder 3 Pro purchase for an additional $299 US. To purchase maintenance, you will need to buy through an Adobe reseller. In the US, please contact CDW at 800-800-4239.
Many, many thanks. This is exactly the information I was looking for.
What if I already have a purchased copy of Flex 3 Pro? I really am bummed that my flash builder beta trial has expired...I heard that if you buy Flex 3 now, they will give you an extension on the trial, but I already have Flex 3, what can I do?
The URL to get a Flash Builder 4 extension serial number (for Flex Builder 3 owners) is http://www.adobe.com/go/flashbuilderextension.
For more information, see http://blogs.adobe.com/flex/archives/2009/06/flash_builder_beta_serial_numb.html.