A couple of interesting articles on the web today. India is planning (no idea how serious the political (i.e., budget) commitment is) a Mars mission and has ideas for asteroid and comet missions (see Space Daily article).
In addition, ESA's Gaia mission will enable new measurements of the effects of Dark Matter on movement of stars in our galaxy (see Space.com article). This isn't a planetary mission, but it is a neat astronomy mission, so I hope you'll appreciate the link. Let me know through comments or e-mails if you'd like future links to astronomy missions. Contact me at vkane56[at]hotmail[dot]com. (And curses to spammers that keep me from just providing a link to my e-mail!)