Used the ppc version for a couple of years, and tolerated the numerous bugs because it is so rich in features. But this version is a total disaster, with frequent crashes and features that dont work right. Guess Ill wait yet another couple of years for the bugs to get worked out. Too bad, because when it works its great. Til then, your money is better spent on a different program.
Update 2/27/2011: This latest version seems much more stable, and I no longer experience crashes. For solar system info, this app is equivalent to an astronomy Swiss Army knife, and I now use it almost daily for that. So Ive changed the rating from 2 to 4. However, the apps organization, UI, and depiction of stars and deep sky are a mess and need serious reworking.
Please note that, in spite of my name "South Star", I am not connected in any way with the firm Southern Stars, although in my opinion their app SkySafari is far and away the best astro app currently available.
South Star about Astromist, v3.0.7