Shadowmeld strength

I'm not sure if this has been posted a million times already, but I've not found any straight answer, so I'll ask anyway. If there already is an answer on these forums, please link me there.
Anyhow, according to http://db.vanillagaming.org/?spell=743 the effect value of active Shadowmeld is only 50. That would make it about as strong as Stealth is at level 10.
Does Shadowmeld scale in some way, or will it remain at effect value 50 still at level 60?
Anyhow, according to http://db.vanillagaming.org/?spell=743 the effect value of active Shadowmeld is only 50. That would make it about as strong as Stealth is at level 10.
Does Shadowmeld scale in some way, or will it remain at effect value 50 still at level 60?