I started using the standard MacBook at work and I quite like it, besides some annoyances I'm trying to solve now (most of them are hardware related, like Apple Keyboard and/or Emacs-like keybindings conflicts etc.)
I am still using my ThinkPad X40 at home, and while I am absolutely in need of Windows apps and love ThinkPad's trackball better than MacBook's (how painful it is to use different keyboards at work and home, especially English vs Japanese), it feels like I should switch to Mac, and the fact is that I own my Mac mini already.
Should I buy a new MacBook (no Air, thanks), or use my work MacBook at home (hmm it's heavy to carry around for 15 minutes every day and night) or keep using ThinkPad and use Mac mini over synergy ... or something else, like eeePC?
The biggest concern about buying new MacBook is that I'll need to sync some desktop data, like that of TaskPaper, Camino Bookmarks and iTunes Library. I guess FolderShare can help on that ...