I consider profitable anywhere from 7 to 9 bitcoins per day. Not 1.
If you don't keep upping your hashrate, you just keep earning less and less each day.
Right now, you need a good 400GH/s to earn 7 to 9 bitcoins per day. Imagine by August. Current ASICS are way overpriced. There is either going to be a huge drop in prices soon or a major disatisfaction from miners earning less than 1 btc per day. (Of course, for previous GPU owners that is an amazing amount of cash for them)
this is exaggerated, earning 1 a day, is respectable, we are talking about $3000 in one months at current price
the problem is the initial investment
if you can mantain this ratio: 3btc/5ghs/10M difficulty then it is possible to buy the next asic , stay in the racing game and make profit
Again, if you are a GPU miner going to an ASIC that is going to be acceptable.
I went directly to an ASIC so my views of what is respectable profit is obviously different. I earned 9btc just two days ago from trading alone. From the ASIC about 3 or 4 BTC in that same day. If I were sticking to only one pool it would have been closer to 2 BTC.
I suspect GPU Miners moving into ASICs are going to settle for far less and perceive 1 BTC per day to be a "good" profit. Heck, Jally owners seem to be pretty happy to even get a quarter of a BTC every other day.