Robinson et al, Buddhist Religions, 5th ed, Wadsworth, Belmont, California, 2004: the s is new to this edition There is a review (Journal of the American Academy of Religion, volume 74 (number 3, September 2006), pages 765-70) of the above book.
The review goes on to compare it with other "new additions to this field":
Olson, The Different Paths of Buddhism, Rutgers University Press, 2005:
Habito, Experiencing Buddhism, Orbis Books, 2005:
Mitchell, Buddhism, Oxford University Press, 2002 (2nd ed 2008):
Review Philosophy East and West, vol 54, pages 269f
Prebish & Keown, Introducing Buddhism, ebook, Journal of Buddhist Ethics, 2005; printed ed, Routledge, 2006: the publishers' blurb, which may or may not have been approved by the authors, calls Buddhism a religion, but the book has no introduction discussing Buddhism as a whole, just launching into historical coverage, arranged similarly to Robinson et al above
The above-mentioned review then goes on to mention
Lopez, Buddhism, Penguin/Story of Buddhism, Harper, San Francisco, 2001: intended primarily for the general reader, so perhaps not strictly a textbook; very impressionistic: gives lots of Buddhist beliefs & practices, but often doesn't say which school(s) they belong to;
Klostermaier, Buddhism, Oneworld Pub, 1999:
Gethin, Foundations of Buddhism, Oxford University Press, 1998:
Keown, Buddhism, Oxford University Press, 1996:
one of the world's leading academic publishers keeps an older book in print:
Harvey, Introduction to Buddhism, Cambridge University Press, 1990:
Going the other way, here's a more recent book:
Cantwell, Buddhism, Routledge, 2010:
Finally, I append here a book that's not a textbook; indeed it might even count as a coffee table book;
Bechert & Gombrich, World of Buddhism, Thames & Hudson, 1984: