Ditto. I run a dual core Athlon64 and 2GB ram. I experienced one Out Of Memory error and several outright crashes. Windows XP has helpfully offered to "Tell Microsoft about this problem" once. (With their Vista woes I'm sure they don't want to know)
Lightroom does something that Bridge never did. If I open an annual folder (say a 2004 images folder) it immediately attempts to render thumbnails of the entire tree, even though I have the 12 months in sub folders and daily shoots sub foldered under that! It's trying to render 8800+ images and dies trying.
I'm using a demo version of LR1.0. I enjoy Lightroom for one specific benefit: offloading memory cards into 2 archives (2 drives) simultaneously, while appending the metadata (adding my copyright info). It's not enough to justify the price.
I can edit RAW files with the CS2 RAW converter, I can sort/tag/rank in Bridge, and I suppose I can make global metadata ammendments in Bridge. LR would save me some steps in the workflow if I could keep it running, but it appears to be leaking all over my RAM. I don't even attempt to run other programs while working in LR.
Not ready for Prime Time.