I like it lots, very useful background reading and I use it for reference occasionally, nice to thumb through and get ideas.

If you make type, it's easily worth the price. But it does need support material, to put things in context:
http://typophile.com/node/15349

hhp

Hey! I thought that you guys agreed that Nick Shinn was a hockey puck, too. Was I mistaken?

I picked the Cheng book up early this year, when I decided it was time to try moving from casual playing around in TypeTool to proper typeface design. For a rank amateur wanting to learn how things actually work, IMO it's fantastic -- simple, easy to read and understand, and full of vital information. It's probably a useful reference even for more experienced designers. It only specifically deals with serif and sans-serif roman letters (no italic, cursive, blackletter, non-Latin languages, etc.) but many of the principles shown seem pretty generally applicable.

I'm definitely going to pick up Bringhurst when I can, but I heard there's a new edition coming out in a few months so I'm waiting for that. I'll add Lawson and Tracy to my list as well... unfortunately, it looks as though the Tracy book is out of print and impossible to find (except in the exhorbitantly expensive rare used books category).

Well, these books are not essentials per se but a good understanding of fine typesetting, historic type style evolution and practical study of great designs is a solid basis for doing worthy type design.

Otherwise you may wind up spendig huge amounts of time inventing boiled water.