Difficulty is growing by leaps and bounds; it's already been rising steadily for a week, and right now it's projected to rise another 11.54% as of the time of this post. ~1.6% is the breakeven point for a 7970 to pay for itself assuming typical PC build and electric prices, so 11.54% is really bad news. But if you think coin prices will grow more than ~50% this year, you are better off buying coins directly and simply holding them rather than getting a trickle of coins and paying monthly power bills.
Right now difficulty is rising from GPUs, but scrypt ASICs are in production and we're probably only a few weeks or months away from seeing the first batches impact difficulty.
https://bitcointalk.org/index.php?topic=355268.0
Doge is still a bit more profitable than LTC if you pump and dump continuously but it won't be for much longer (maybe not even tomorrow) if it keeps falling while LTC goes up in value even with the crazy difficulty increases.
http://www.coinwarz.com/cryptocurrency
I pretty much just try to follow coinwarz and pump and dump as I go. Fastcoin was pretty promising but the rounds are so short that getting consistent shares is hard.
Mine and sell as you go is what you mean. "Pump and dump" means someone buying a lot of something (in this case, a coin) and then trying to get other people to buy it too, then if the price goes up, quietly selling the coin, leaving the new buyers with a bunch of devalued coins. You see a lot of that crap on online forums. Btw, sites like coinwarz calculate instantaneous numbers but price and difficulty and trading volumes vary wildly over time, so be very careful assuming that mining the top coins is worth it. Many times what is no. 1 now will be no. 18 later in the day, as an example. Due to transaction fees/exchange fees, higher stales/orphans, scammer or hacked pools etc. it's possible to make less mining altcoins than straight up LTC even if the altcoin looks more profitable on paper.