Presently as a Destruction warlock raiding in cataclysm, you really have two options for a glove enchant.
The first, most standard would be 28 sp. The Second being 50 haste. I am aware 28 sp is a wrath enchant, but it is significantly better than a mastery enchant of any kind, and pulls ahead of a haste enchant if you aren't within 50 haste of another immolate tick.
To corroborate my statement I have provided a link to the Elitistjerks thread on destruction warlocks
I wish to see it updated that 28 sp get credited as a 20 point enchant instead of 15.