A short time ago I upgraded the drive in my macbook pro as I had filled up the stock 250GB drive that came with it. After a little research I opted for the WD scorpio blue WD10TPVT 1 TB, as I had found out that even with it's increased height, it would still fit the macbook. But, after only a few months of use the drive has failed.
Fortunately the inbuilt S.M.A.R.T. check threw up an error message informing me of the impending doom, and advised me to back up my data pronto. As I could not get to a store until the weekend, I carried on using the drive for the rest of the week with no issues except running a tad slow.
One interesting thing that I noticed, is that, even though using OSX's 'Disk Utility', showed a S.M.A.R.T. failure (S.M.A.R.T. is a hardware check carried out by onboard diagnostics within the drive unit), Tech Tool's S.M.A.R.T. test passed as okay.
So, I went out at the weekend to buy a replacement drive, and to post the failed unit off for warrantee repair, as it is covered for 3 years. Unfortunately the store did not have a 1TB unit, so I purchased a WD 500GB black unit instead. Interestingly the store owner commented that they had stopped stocking the larger drive due to the high failure rate. It seems that this is one of those cases where bigger is most definitely not better.
My guess is that the larger drive is more fragile than its smaller counterparts and had failed as a result. I travel quite a lot, and so I quite often pack up my macbook whilst it is in standby / sleep mode, normally this is no issue, but I think in this case, with the more fragile drive, it simply did not fare too well.
So if you're thinking of upgrading to a 1TB drive, consider how your laptop will be treated, as it might mean your drive fails sooner than expected.