Flash and Lion don’t like each other yet, but that’s just the beginning.
Adobe has posted a list of known issues with Lion, and it seems to cover most, if not all of, Adobe’s product line. As website tauw points out, it’s a real letdown that Adobe hasn’t been able to correct these problems over the course of the Lion developer preview.
As for Flash player, hardware acceleration is disabled, causing issues. Most importantly, Adobe’s Creative Suite has issues as well. Photoshop gurus beware for now. Read up on the known issues before jumping to Lion.
Here is a list of software with known issues: Acrobat family, Adobe Drive, Contribute, Dreamweaver, Fireworks, Flash Builder, Flash Catalyst, Flash Player, Illustrator, Lightroom, LiveCycle, Photoshop and Premiere Pro.