The transition to an x86-based architecture from PowerPC has been quite a smooth one for me. I'm not a heavy Photoshop user, so it runs quite fast enough for my needs under Rosetta. Office too runs quite speedy under Rosetta. Other than these applications, most of the ones I use are available now as Universal binaries. Everything seemed to be available except for a good Lisp compiler for Intel Macs.
I had tried installing GNU CLisp via DarwinPorts but was told it is not available for Intel-based Macs. I'd also tried running Lispworks Personal Edition but it has known issues on Intel-based Macs and seems to randomly hang for a minute or two at a time. So the two Lisp implementations I'm most familiar with are not yet available for the Mac.
After searching long and wide, I found a couple of options. Franz offers Allegro Common Lisp 8.0. For those that want something a little easier on the wallet, Steel Bank Common Lisp, which is both open source and free (as in beer), is also compatible with Intel-based Macs.
So sbcl it is for me, at least for the time being. Lispworks should be out with a Universal binary version of their implementation very soon (2Q 2006) and I am sure Darwinports will get a compatible version of clisp soon enough as well.