yes, i have been working and living in london for more than 1 year under a highly skilled migrant programme (HSMP) and i subsequently switched to Tier 1 (General).

bear in mind - i got my visa way before the uk recession and jobs were easy to come by. now unemployment is a big issue here. you won't be able to renew the tier 1 visa without a skilled job.

anyways, it is unlawful to reject your application if you :-
1) have met the minimum 75 points
2) can proof that you meet the required English standard
3) have minimum funds of GBP2800.
4) obviously, you must not have any prior criminal convictions or have previously abused your immigration status(i.e. overstayed on a visa, outstanding fines in uk, etc)

don't bother applying if you don't meet the above. for me, application to approval took 3 weeks, applying from KL, Malaysia.

for precise requirements and how points are calculated, see http://www.ukvisas.gov.uk/en/howtoapply/infs/inf21pbsgeneralmigrant#6375036

good luck.

~Live like there's no tommorrow~