I would say most definitely. Last year they re-introduced their two kit lenses, the 18-55mm and 50-200mm, in a WR version(their term for weather resistant). I bought the 18-55mm WR and it is very well built for a 'kit lens', and though I haven't had it in the rain, I have read multiple user experiences that indicate it is well sealed and can handle moderate sustained rain without problems. Prior to the newest cheaper WR lenses, the DA* lenses, which are their upper line of lenses, have been around for several years and are also completely weather sealed - the focus and zoom are internalized so there are no extending parts (so the DA* lenses are supposed to be better - they are sold as weather sealed, vs. the newer cheaper lenses which are sold as being weather resistant). I have the DA* 50-135mm f2.8, and it is easily my favorite lense, with great optics and I have personally taken it out in several downpours just for fun! Works as good as new. Pentax is also releasing the new 18-135mm WR lens announced at Photokina, and their DFA 100mm Macro lens was also re-released last year in a weather sealed package.
They have also been making sealed bodies for close to 5 years now. Starting with the K10d, then K200d and K20d, the K7 and now K5. The older K10d and K200d can be found used from $300-400 and the K20d around $500 - pairing one of those with the newer 18-55mm WR lens gives you a weather sealed kit for potentially well under $600.
The new D7000 from Nikon is reportedly also weather sealed - attaching a non-sealed lens to a sealed body is worthless though IMO, and a sealed lens from Nikon will cost dearly!