If any have been suggesting decreased frequency of rain / snow, they evidently have no credibility whatsoever. For a start, ocean temperatures as measured both directly and via satellite telemetry have a long-term rising trend, although as with any temperature measurement you have to look at several decades worth of measurements to get the overall picture to mitigate against seasonal trends, day/night variation, and the effects of El Nino / El Nina etc. I'd say ocean temperatures are likely to be more reliable than land measurements as the latter can be affected by terrain, development, land use, possibly even soil type.
However, as anyone familiar with the water cycle should know, if ocean temperatures rise there'll be more evaporation, which would lead to more clouds and more precipitation.
Meanwhile, in the UK at least over the past decade or so, while the average annual rainfall hasn't varied that much, the patterns have: rather than being spread throughout each month, typically the majority of the month will be dry, and the monthly quota will be dumped over the course of a couple of days, leading to surface flooding (as the storm drains weren't designed to cope with that kind of load). On a slightly more long-term trend, 2009-11 were significantly drier than average and by March 2012 many reservoirs were at least 6 feet below "normal" levels, leading many companies to impose hosepipe bans. Nature then decided to play a practical joke with the three wettest months on record...
I've said it elsewhere, but while I believe the earth is warming, I also believe there's b****r all we can do about it. However, with an ever-expanding human population, one thing someone will have to do at some point (but goodness knows how!) is try and limit our ever-expanding per capita
resource usage (not only are there more humans on the planet, but on average each human uses more resources than they did in previous decades - air con, food, electronic gadgets etc...)