A great deal has been written about angel investing in recent years. Angel investing has become the sport of choice for many successful entrepreneurs in Silicon Valley (e.g., Dave Morin, Chris Michel, Ariel Poler, etc.). What's more, it has spawned a whole new class of venture funds — once called Super Angels, now called Micro VCs (e.g., First Round Capital, True Ventures, SoftTech VC, etc.). And now traditional venture investors (e.g., Greylock Capital, Andreessen Horowitz, CRV, etc.) have created programs to invest small amounts of money in large numbers of startups. Unfortunately, as seed investing moves from a boutique practice to more mass market, its value is diminished dramatically.
As a general matter, I think that more seed funding is a great thing. It is certainly beneficial — often times essential — for small companies to raise a little bit of money to help validate an idea or market. But historically one of the most valuable things about angel investment was that it was accompanied by an angel. That angel wouldn't just invest in the company, he or she would serve as an indispensable advisor to the company as well. Not only did you get money to propel your business forward, you also got the help of someone who had run the startup gauntlet before you.
Regrettably, what once was a boutique business has in many instances become mass market. While there are some angels and Micro VCs can provide meaningful time and attention to their entrepreneurs, there are a number of folks out there who think that angel investing is a volume business. Needless to say, as the number of companies financed by any given investor grows, the amount of help that investor can give to each company diminishes proportionally. These investments become more about the placing of bets than they do about helping entrepreneurs succeed.
Sure, some of these stock pickers will make some good bets and even make some money. But it won't be any thanks to them. As a general matter, early stage entrepreneurs don't just need money, they need help and advice. And if help is no longer part of what you get from your seed investors, I believe the likely success of those investments will diminish.
Worse yet, taking seed investment from traditional venture investors can be counter-productive. It is impossible to imagine how a VC firm that is investing in dozens of early stage startups can find the time to be helpful while also working with their more traditional portfolio. You may get a little of their money and a little of their reputation, but you will get at the expense of any real help in building your business.
So why have VC funds started investing in seed rounds? They do it because they think it gives them an option on future financings. By putting a little bit of money into a company's seed round, they get a seat at the table. And from that seat, in theory, they can keep track of how well it is going and preemptively finance the "best" companies that they've seed funded. The only problem with the theory is that these traditional VCs don't have the time or capacity to actually keep track of all the companies they've seed funded. So they aren't capable of being pre-emptive. Instead, they expect an early look at any Series A financing, despite the fact that they haven't earned the right by actually being helpful to the companies they have seeded.
More importantly, traditional VCs are incapable of providing one of the most important and valuable angel services — introductions to future investors. As is becoming increasingly clear, investment is the life blood of the startup world. The problem that companies seed funded by traditional VCs have is that there is a natural assumption that any company that does not receive follow-on funding from its earlier VC investor is fundamentally broken. There is virtually nothing that a VC can say in his or her introduction to other investors that won't raise eyebrows. So taking angel money from a traditional venture investor is a bet on that firm funding your Series A. Unfortunately, if that doesn't work out, you're back is up against the wall. 
It is true that money is fungible. But investors are not. The choices you make when raising seed capital can have a meaningful impact on the long-term success of your startup. So find investors who will bring you value beyond the dollars in your bank account. Find investors with the time and inclination to help you. Find investors who will increase your chances of raising additional capital, not diminish those chances. Great angel investors are invaluable. So pick your partners well.
 On the rare occasion that my partners and I seed fund a startup, we work hard to alleviate the concerns I've described above. We only invest in a very small number of seed stage opportunities and we commit meaningful time and attention to those businesses, often going on the board (for example, I was the earliest investor in the likes of WePay and Splunk). Moreover, we take a substantial lead role in the seed financing, so there is no negative presumption when we introduce the company to our VC friends for the next round of financing. We will invest along side the new VC, but have no need to lead the Series A ourselves. Needless to say, this approach won't scale to dozens of startups. But it will increase the likelihood that those business we seed fund are successful.