I updated to Ubuntu 9.04 with some hassle. I took a deep breath and went for the amd64-version, and so far it has been a little struggle with Flash, but that's all. The system feels a bit more responsive.
But a friend of mine reminded me of the thing with mono+WinForms: winforms isn't installed by default in Ubuntu. This is disappointing, as it means apps targeting windows+ubuntu will have to distribute the winforms/mono DLLs or else have separate installs/zips/debs for each OS.
In the long rung, having a single .ZIP for the whole application might be too simplified. After all, to use sound in the app definitely means separating the distribution files per OS.
Oh well just some whining :) Have to learn how to create .deb files (Mac guys out there: what is a good redistributable format for you?)