I've got a few blossoms right now on blueberry, pluot, nectarine, and grape. It's fairly common and not usually any concern. Usually it's a small percentage of what will bloom next spring and therefore not an issue. Even in warm winter areas the resulting fruit doesn't ripen to good quality. Pinch them off if it makes you feel better.

It's more common on low chilling fruit in warm climates and is often favored by pruning or rain after a dry spell.