Can casual people still mine for bitcoins, now that the difficulty is much higher than it was? Can casual people still mine for bitcoins? As of October 2012, the difficulty seems very high, being over 3,000,000.

I've seen a ad for bitcoins, and watched the video. It said I could mine for them with my computer, so can I?
Well, you can TRY mining. To see how much coins you can expect, check your computer's GPU on the Wiki page, get its hash rate, and plug that into a profitability calculator, such as mine. This can give you an idea of how many coins can you expect to mine and whether you would get any profit from that.

Unfortunately, most likely you won't be able to mine at a profit using a PC. Bitcoin's difficulty is quite high, the reward will be dropping by half soon, and with the introduction of ASIC miners, GPU mining will be outclassed. However, if you are willing to invest some money into custom hardware, you can still start your career as a full-time Bitcoin miner. But again, you ought to check if it calculates for you.

However, if you want to try your luck at a newly emerging trend of using your GPUs to "mine" for split-key vanity addresses, you can check out my Vanity Pool, or its topic on BitcoinTalk. The process is quite similar, but the profit margin can be better.